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what you shouldn’t. ules uggestions tarving ead lear * 中国英语教师网 You mustn’t go swimming immediately after lunch. Yes, and you mustn’t go swimming on you own. You must always go with someone. Work with another pair. Find out what rules and suggestions they have made in their list. Welcome to Hainan! Work in groups. You may choose one place of interest and write some advice for visitors to China. (at least five pieces of advice)
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pay attention to
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正在加载中，请稍后...Generate dynamic SQL statements in SQL Server - TechRepublic
When you need to solve a tricky database problem, the ability to generate SQL statements is a powerful tool — although you must be careful when using it. This article explores how you can use this functionality to generate SQL statements on the fly.
Dynamic SQL statements
A dynamic SQL statement is constructed at execution time, for which different conditions generate different SQL statements. It can be useful to construct these statements dynamically when you need to decide at run time what fields to bring back from SELECT the different crite and perhaps different tables to query based on different conditions.
These SQL strings are not parsed for errors because they are generated at execution time, and they may introduce security vulnerabilities into your database. Also, SQL strings can be a nightmare to debug, which is why I have never been a big fan of dynamically built SQL however, sometimes they are perfect for certain scenarios.
A dynamic example
The question I answer most often is, "How can I pass my WHERE statement into a stored procedure?" I usually see scenarios similar to the following, which is not valid TSQL syntax:
DECLARE @WhereClause NVARCHAR(2000)
SET @WhereClause = ' Prouct = ''Computer'''
SELECT * FROM SalesHistory WHERE @WhereClause
In a perfect world, it would make much more sense to do the following:
DECLARE @Product VARCHAR(20)
SET @Product = 'Computer'
SELECT * FROM SalesHistory WHERE Product = @Product
It isn't always this easy. In some scenarios, additional criteria is needed, and as tables grow wider, more and more criteria is often needed. This can typically be solved by writing different stored procedures for the different criteria, but sometimes the criteria is so different for each execution that covering all of the possibilities in a stored procedure is burdensome. While these stored procedures can be made to take into account every WHERE statement possible depending on different parameters, this often leads to a degradation in query performance because of so many conditions in the WHERE clause.
Let's take a look at how to build a simple dynamic query. First, I need a table and some data to query. The script below creates my SalesHistory table and loads data into it:
CREATE TABLE [dbo].[SalesHistory]
[SaleID] [int] IDENTITY(1,1),
[Product] [varchar](10) NULL,
[SaleDate] [datetime] NULL,
[SalePrice] [money] NULL
SET NOCOUNT ON
DECLARE @i INT
SET @i = 1
WHILE (@i &=5000)
INSERT INTO [SalesHistory](Product, SaleDate, SalePrice)
VALUES ('Computer', DATEADD(ww, @i, '3/11/1919'),
DATEPART(ms, GETDATE()) + (@i + 57))
INSERT INTO [SalesHistory](Product, SaleDate, SalePrice)
VALUES('BigScreen', DATEADD(ww, @i, '3/11/1927'),
DATEPART(ms, GETDATE()) + (@i + 13))
INSERT INTO [SalesHistory](Product, SaleDate, SalePrice)
VALUES('PoolTable', DATEADD(ww, @i, '3/11/1908'),
DATEPART(ms, GETDATE()) + (@i + 29))
SET @i = @i + 1
Now I will build my stored procedure that accepts a WHERE clause. For the purpose of this example, I will assume that the WHERE clause was built dynamically from the calling client application.
CREATE PROCEDURE usp_GetSalesHistory
@WhereClause NVARCHAR(2000) = NULL
DECLARE @SelectStatement NVARCHAR(2000)
DECLARE @FullStatement NVARCHAR(4000)
SET @SelectStatement = 'SELECT TOP 5 * FROM SalesHistory '
SET @FullStatement = @SelectStatement + ISNULL(@WhereClause,'')
PRINT @FullStatement
EXECUTE sp_executesql @FullStatement
—can also execute the same statement using EXECUTE()
EXECUTE (@FullStatement)
I set the @WhereClause parameter to allow NULL values because we may not always want to pass a value in for the @WhereClause.
For every execution of this stored procedure, every field is returned for the TOP 5 rows from SalesHistory. If there is a value passed in for the @WhereClause parameter, the executing statement will append that string to the @SelectStatement string. Then I use the stored procedure sp_executesql to execute the dynamically built SQL string.
sp_executesql or EXECUTE()
There are two ways to execute dynamic SQL in SQL Server: use the sp_executesql system stored procedure or the EXECUTE() operator. Sometimes the two methods can produce the same result, but there are differences in how they behave.
The system stored procedure sp_executesql allows for parameters to be passed into and out of the dynamic SQL statement, whereas EXECUTE() does not. Because the SQL statement is passed into the sp_executesql stored procedure as a parameter, it is less suseptible to
than EXECUTE(). Since sp_executesql is a stored procedure, passing SQL strings to it results in a higher chance that the SQL string will remain cached, which should lead to better performance when the same SQL statement is executed again. In my opinion, sp_executesql results in code that is a lot cleaner and easier to read and maintain. These reasons are why sp_executesql is the preferred way to execute dynamic SQL statements.
In my previous example, I looked at how you can build a simple SQL statement by passing a WHERE clause into a stored procedure. But what if I want to get a list of parameter values from my dynamically built SQL statement? I would have to use sp_executesql because it is the only one of my two options that allows for input and output parameters.
I am going to slightly modify my original stored procedure so that it will assign the total number of records returned from the SQL statement to an output parameter.
DROP PROCEDURE usp_GetSalesHistory
CREATE PROCEDURE usp_GetSalesHistory
@WhereClause NVARCHAR(2000) = NULL,
@TotalRowsReturned INT OUTPUT
DECLARE @SelectStatement NVARCHAR(2000)
DECLARE @FullStatement NVARCHAR(4000)
DECLARE @ParameterList NVARCHAR(500)
SET @ParameterList = '@TotalRowsReturned INT OUTPUT'
SET @SelectStatement = 'SELECT @TotalRowsReturned = COUNT(*) FROM SalesHistory '
SET @FullStatement = @SelectStatement + ISNULL(@WhereClause,'')
PRINT @FullStatement
EXECUTE sp_executesql @FullStatement, @ParameterList, @TotalRowsReturned = @TotalRowsReturned OUTPUT
In the above procedure, I need to declare a parameter list to pass into the sp_executesql stored procedure because a value is being assigned to the variable at run time. The only other change to the sp_executesql call is that I am assigning the output parameter from the call to the local @TotalRowsReturned parameter in my usp_GetSalesHistory stored procedure.
I can even call my usp_GetSalesHistory stored procedure similar to the way I did before, but with the addition of an output parameter to indicate the rows that were returned.
DECLARE @WhereClause NVARCHAR(2000), @TotalRowsReturned INT
SET @WhereClause = 'WHERE Product = ''Computer'''
EXECUTE usp_GetSalesHistory
@WhereClause = @WhereClause,
@TotalRowsReturned = @TotalRowsReturned OUTPUT
SELECT @TotalRowsReturned
Although I am not a huge fan of using dynamic SQL statements, I believe it is a great option to have in your tool belt.
If you decide to incorporate dynamic SQL into your production level code, be careful. The code is not parsed until it is executed, and it can potentially introduce security vulnerabilities that you do not want.
If you are careful with your dynamic SQL statement, it can help you create solutions to some pretty tricky problems.
a SQL Server database administrator and consultant who works for a bank in Louisville, KY. Tim has more than eight years of IT experience, and he is a Microsoft certified Database Developer and Administrator. If you would like to contact Tim, please e-mail him at .
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About Tim Chapman
Tim Chapman is a SQL Server MVP, a database architect, and an administrator who works as an independent consultant in Raleigh, NC, and has more than nine years of IT experience.
Tim Chapman is a SQL Server MVP, a database architect, and an administrator who works as an independent consultant in Raleigh, NC, and has more than nine years of IT experience.
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Delivered Fridays> 【答案带解析】You must be careful when you swim the la...
You must be careful when you swim
the lake.A. across
B. belowC. over
D. through 
试题分析：考查介词。句意: 当你游过这条湖时一定要小心。below在……下面; over在……上面; through透过, 穿过; across穿过, 从表面穿过。根据句意可知是在湖的表面穿过。故选A。
考点分析：
考点1：介词和介词短语
介词是一种用来表示词词, 词与句之间的关系的词。在句中不能单独作句字成分。介词后面一般有名词代词或相当于名词的其他词类，短语或从句作它的宾语。介词和它的宾语构成介词词组，在句中作状语，表语，补语或介词宾语。
介词分类及用法
&&&&&&& 一、表示时间的介词
&&&&&&&& 时间介词有in , on，at， after， since，during,by,before,after,until等，前三个介词用法有个口诀： at午夜、点与分，上午、下午、晚用in。
&&&&&&& 年、月、年月、季节、周，之前加上介词in。
&&&&&&& 将来时态多久后，这些情形亦用in。　
&&&&&&& 日子、日期、年月日，星期之前要用on。
&&&&&&& 其余几组常见的时间介词辨析如下辨析如下：
&&&&&&& 1、时间介词in与after 的用法辨析
&&&&&&&& 介词 in + 一段时间用于一般将来时。如：We’ll go to school in two weeks.
&&&&&&&& 介词after + 一段时间用于一般过去时。如：My mother came home after half an hour.
&&&&&&&& 介词after + 时间点常用于一般将来时。如：We’ll go out for a walk after supper.
&&&&&&& 2、时间介词for与since的用法辨析
&&&&&&&& 介词for 表示一段时间如：I have been living here for 10 years.
&&&&&&& 介词since 表示从过去某一时间以来如：I have been living here since 2000.
&&&&&&& 3、时间介词before与by的用法辨析
&&&&&&& 介词before表示“在…之前”如：He won’t come back before five .
&&&&&&& 介词by表示“到…时为止，不迟于…”如：The work must be finished by Friday.
&&&&&&& 4、时间介词during与for的用法辨析
&&&&&&& 当所指的时间起止分明时用介词during如：He swims every day during the summer.
&&&&&&& 如果一段时间不明确则用介词for如：I haven’t seen her for years.
&&&&&&& 5、时间介词till与until用法的异同
&&&&&&& till和until用在肯定句中，均可表示“直到…为止”，如：I will wait till（until）seven o'clock．
&&&&&&& till和until用在否定句中，均可表示“在…以前”或“直到…才”。
&&&&&&& 如：Tom didn't come back till（until）midnight．
&&&&&&& till多用于普通文体，而 until则用于多种文体，并且在句子开头时，用until而不用till如：Until he comes back，nothing can be done．
&&&&&&& 注意：在last, next, this, that, some, every 等词之前一律不用介词。
&&&&&&& 二、表示方位的介词
&&&&&&& 常用的表示方位的介词用法及辨析如下：
&&&&&&& 1、方位介词on, over, above的用法辨析
&&&&&&& 介词on表示一物放在另一物上面，两者紧贴在一起，如：The book is on the table.
&&&&&&& 介词over表示一种垂直悬空的上下关系，即“在…上方”，如：Is there any bridge over the river?
&&&&&&& 介词above表示一般的“高于…”，“在…之上”，如：There was an electric clock above his bed.
&&&&&&& 2、方位介词under与below的用法辨析
&&&&&&& 介词under是over的反义词即“在…下方”，如：They were seen under the tree.
&&&&&&& 介词below是above的反义词即“低于…”，“在…之下”，如：They live below us.
&&&&&&& 3、方位介词across,、through、over,、past的用法辨析
&&&&&&& 介词across着重于“从一头或一边到另一头或另一边”，强调从表面穿过。
&&&&&&& 如：She went across the street to make some purchases.
&&&&&&& 介词through着重于“穿越”，强调从一定的空间内穿过。
&&&&&&& 如：The sunlight was coming in through the window.
&&&&&&& 介词over多表示从“上方越过”，如：He failed to
he had to go round it.
&&&&&&& 介词past表示从“面前经过”，如：Someone has just gone past the window.
&&&&&&& 4、地点介词at与in的用法辨析
&&&&&&& 介词at表示较小的地方，如家、村、乡村等，如：He lives at a small village.
&&&&& &&介词in表示较大的地方，如大城市、国家、洲等，如：He lives in Beijing.
&&&&&&& 5、表示东南西北的时候，地点介词in、on、to的用法辨析
&&&&&&& 介词in表示“包含”如：Beijing is in the north of China.
&&&&&&& 介词on表示“紧邻”如：Canada lies on the north of the U.S.
&&&&&&& 介词to表示“没接触”如：France lies to the south of England.
&&&&&&& 三、表示方式、手段、或工具的介词by,in,on,with.
&&&&&&& 1、by,in,on,表示交通方式。用by 时，交通工具前不用任何词；用 in和on 时，交通工具前用冠词或形容词性物主代词。例如by car=in a car,by bike=on a bike.
&&&&&&& 2、表示手段或工具，with后跟具体工具，如Iin表示使用某种语言或墨水、颜色等原料，例如：in English.
&&&&&&& 四、介词的固定搭配
&&&&&&& across from在对面&& look for 寻找& look after 照顾 get on with 与某人相处
&&&&&&& agree with 同意（某人）&& arrive at(in) 到达 ask for 询问&& begin…with 从……开始 believe in 相信&&& break off 打断&& break out 爆发 bring down 降低&& bring in 引进 bring up 教育，培养&& build up 建起 burn down 烧光&& call back 回电话 call for 要求约请&&& call on 拜访 访问&& care for 喜欢 carry on 继续开展&& carry out 实行开展 check out 查明 结帐&&& come about 发生，产生&& come out 出来&& come to 共计 达到 compare…with 与……比较&& compare to 比作 cut off 切断&& date from 始于 depend on 依靠&& devote to 献于 die out 灭亡&& divide up 分配 dream of 梦想&& fall off 下降 fall over 跌倒&& feed on 以……为食 get down to 专心于&& get through 通过
&&&&&&& 对于介词的考察，通常是以单项选择或完形填空形式考查介词用法，尤其是几个易混淆的代词。另外，介词与动词和形容词构成的固定搭配也是常见的考试内容。
&&&&&&& 1、掌握介词固定搭配
&&&&&&& 2、准确把握介词及介词短语的基本意义和用法。
&&&&&&& 典型例题1：Peter usually gets up early&&&& the morning.
&&&&&&&&&&&&&&& A& in&&&& B on&& C& at&&&& D& of
&&&&&&&& 解析；这是2008年北京市的一道中考题，本题考查时间介词的用法。“在早上”应为in the morning.
典型例题2：-How do you usually go to school?
&&&&&&&& -&&&&& my bike.
&&&&&&& A& By&&& B& In&&&& C& On
&&&&&&& 解析；& 虽然介词by表示“乘坐”，但是它所接的名词前没有限定词，即by bike.而本题中bike 前有限定词my，这时应用on.
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students in our school bought it.A. three hundred
B. three hundreds
C. hundred of 
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very much.A. he
B. hisC. him
D. himself 
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.A. dictionary
B. magazineC. newspaper
D. guidebook 
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musician like Lang Lang.A.
书面表达。假设你是李华, 上周末你参加了一次郊游(outgoing)。请根据下面表格中的提示信息写一篇题为“A pleasant outgoing”的英语短文, 参加某英文报纸的征文比赛。A pleasant outgoing时间上周末参加者你和……地点北山公园(the North Hill Park)活动骑自行车、爬山、野餐、做游戏……感受……要求: 1. 不要逐条翻译表格中的信息, 可适当增减内容;2. 短文中不得出现真实的地名、人名和校名;3. 词数: 80～110个。参考词汇: go for an
have a picnicA pleasant outgoing______________________________________________________________________________________________________________________________________ 
题型：单项填空
难度：中等
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Find something to grip the jar with. Jar lids are slippery, and it can be difficult to get a good grip on them using your hands alone. Gripping the lid with something aside from your fingers can make it can make it much easier to successfully open a finicky jar. Grab one of the these items to help you get a grip:
A rubber jar opener
A rubber glove
A silicon pad
Grippy shelf liners
A wide rubber band
Grip the lid with your chosen item. Place your palm on the top of the lid and apply pressure. Grasp the edges of the jar with your fingers. Use your other hand to hold the jar steady.
to Open a Difficult Jar
Twist off the lid. Most jar lids open by twisting to the left (counterclockwise). Keep a firm grip on the jar to avoid spilling its contents. Alternatively, you can grip the lid firmly and apply force on the jar instead of the lid. If you're still having trouble opening the jar, move on to a method that breaks the seal.
Hold the jar tightly in your non-dominant hand. Hold it at a 45-degree angle with the bottom exposed.
to Open a Difficult Jar
Slap the bottom of the jar with the center of your palm. This causes a water hammer effect, raising the pressure near the lid and breaking the vacuum. Only slap hard enough to break the seal, but not hard enough to hurt your hand or break the jar. You should hear a "pop" sound when the seal breaks.
to Open a Difficult Jar
Unscrew the lid. Hold the jar upright and turn the lid to the left. It should come off without trouble if the seal was successfully broken.
to Open a Difficult Jar
Dent the edge of the jar lid with a firm object, preferably a spoon handle or the dull-side of a table knife's blade. Hold your spoon at a 45-degree angle. Use it to strike the side of the jar lid hard enough to make a slight dent. Rotate the jar about an inch and strike it again. Continue to dent the lid until you've gone all around and you hear the seal pop.
Make sure you hold the jar tightly with your other hand, so the jar doesn't fall over and break when you strike it.
Be careful not to strike the jar itself, or strike too hard. The jar could shatter.
to Open a Difficult Jar
Unscrew the lid. Once you hear the seal pop, hold the jar upright in one hand. Use the other hand to turn the lid to the left and remove it. Check the jar's rim to make sure it did not get chipped before using the contents of the jar.
Heat a small amount of water until it is hot, but below boiling point. You only need enough water to cover the lid when you turn the jar upside down into the water pot. Turn off the heat when the water is hot.
Hot tap water will also do the trick, especially if the jar is cold to start. Fill a small bowl with enough hot tap water to cover the lid.
Or you can simply run hot tap water over the lid, making sure it doesn't touch the rest of the jar.
to Open a Difficult Jar
Place the jar upside-down in the hot water. Make sure the lid is submerged, but the jar itself is not covered in hot water. The hot water will make the lid expand temporarily and break the seal. Let the lid sit for one to two minutes, until you hear the seal pop open.
to Open a Difficult Jar
Open the jar. Hold the jar upright, wipe off the water, and open it up. The lid should screw off easily once the seal has been popped. The heat may have melted the contents of the jar.
Grab a utensil you can use to pry up the lid. You can use a number of different kitchen utensils to break the seal. Try one of these:
A butter knife
A teaspoon
An old-fashioned triangle can opener
A bottle opener
Any other strong, thin-tipped object
Place the edge of the utensil under the lid of the jar. Stick it into the place where the bottom of the lid juts over the mouth of the jar. Push the utensil until it is firmly wedged between the lid and jar.
to Open a Difficult Jar
Push the utensil up and out to loosen the jar. Apply force to the utensil like a lever. Separate the lid from the jar a little to break the seal. Scoot the utensil over and do the same in another spot. You should hear a "pop" sound when the seal breaks.
Be careful! Thin glass jars could crack, plastic could puncture.
to Open a Difficult Jar
Unscrew the lid. Once you hear the seal pop, hold the jar upright in one hand. Use the other hand to turn the lid to the left. It should come off easily with a gentle twist.
Get a hair dryer or another source of direct heat. Heating the lid will cause it to slightly expand, breaking the seal. It can also help melt jam or other food that may cause a lid to stick.
This method may only be used to open jars with metal lids. Do not heat plastic lids, as they may melt.
Only use this method as a last resort. Heating a jar lid can cause it to become hot enough to burn your skin. Be very careful when handling the jar.
Blow hot air around the edge of the lid. Do this just long enough to heat the lid. Don't hold it for too long in any particular place, or the lid could warp.
to Open a Difficult Jar
Open the lid with a towel or glove. Don't place your hand directly on the lid, since it will be very hot. The lid should easily twist off. The heat may have melted the contents of the jar.
What if the item I am trying to get the lid off of is refrigerated? Can I still use heat to get the lid off?
If it's glass, you should be very, very careful not to let the hot water touch the cold glass. This could cause it to shatter. Avoid using direct heat on it for the same reason. Try a damp towel to grip the lid and turn. Most refrigerated jars have been opened already, and may be stuck because of dried food or condiments between the lid and the jar. Try using warm water, instead of hot to try to rehydrate the dried bits and make it easier to twist the lid.
How do I open a plastic bottle that has been refrigerated?
wikiHow Contributor
Using a wet towel on the cap, hold the bottle from the bottom and twist open the lid.
How can I break the seal that holds all the pressure in the jar?
wikiHow Contributor
You could use a special seal breaking tool, or drive a butter knife under the lid to break the seal. When using a knife, you should be very careful.
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If you’re having trouble opening a jar, try using a rubber glove or a wide rubber band to help you get a grip on the lid as you twist it. If that doesn’t work, hold the jar tightly in your non-dominant hand and tilt it at a 45-degree angle so you can see the bottom. Then, slap the bottom of the jar hard enough to break the vacuum seal, but not hard enough to hurt your hand or break the jar. If it works, you should hear a pop, and the lid should come off easily.
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The vacuum seal is made worse by refrigerating the jar, so try to open the jar before refrigerating.
Mason/Ball jars have an separate threaded ring which moves independently of the dome cap. The cap is held fast by the vacuum formed in the jar, and a ring of sealant that softens during the canning process. Heating the lid of a dome-sealed jar with hot water will soften the sealant, making it easier to remove the lid. You can also use a bottle cap opener to gently pry the edge of the lid up to break the seal and release the vacuum.
The striking method is not only useful for breaking the seal, but it'll also help if food is stuck in the lid. Warmer temperatures may also help soften any food that's preventing the lid from twisting.
If you don't intend to reseal the lid, puncture it with the back end of a chef's knife. This will break the seal with the least effort, but render the lid useless.
Wear rubber gloves.
Hit the lid's corner in several places using a spoon, but no more than the spoon's weight. After a few hits, if you are not lucky enough to see the lid just pop up the jar, it should be easier to unscrew it.
If the cap is small enough for a nutcracker to fit around it, this works like a peach.
Or...Try moving your hand to a different spot on the lid before trying again. This can sometimes make an 'impossible to open' ja it's all in the angle of attack, so to speak.
If you chose to strike the lid with another object, check the rim after removing the lid for chips of glass that may have broken off (could be in food).
Be careful not to crack the jar, or else it could break while you're twisting it and cut your hand. This is another reason why gripping the lid with a cloth might be a good idea.
Be careful when using butter knives to open a jar - they may not seem sharp, but if one slips while you are applying force to it, you can experience a very nasty cut.
Don't strain yourself! If all else fails, find someone with strong arms.
The cap of a Mason or Ball jar is held fast by the vacuum, and a ring of sealant that softens during the canning process. Heating the lid of a dome-sealed jar with a flame might melt the sealant to a liquid and contaminate the contents of the jar.
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of How to Open a Difficult Jar was reviewed by wikiHow Test Kitchen on April 2, 2015.
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"I couldn't believe that wearing a rubber glove and twisting would work. This was after I tried someone with stronger hands, smacking bottom of glass with my hand, tapping off work surfaces, using dishcloth/rubber bands for stronger grip and hot water."..."
Koustuv Garai
"I struggled for a day to open a new jam jar. At last, I got dejected and searched in internet. The innovative method of dipping the lid of jar in hot water is an excellent way. I was able to break the vacuum seal and open the jar without effort. Thanks."..."
Norman Babcock
"My drawer liner isn't even particularly &grippy& and it still worked super easy and fast! I was trying to get that jar open for days with just my hands and force. I wouldn't have even thought of it without this article, thanks!"..."
Margo Barron
"In the end, it was using a spoon as a lever to break the seal. Previously I tried the hot water and utensil strike on the lid. Great illustrations and helpful hints in this article."..."
"Very stuck lid, but the spoon under the edge to pop the seal worked like a treat! We worked through the various methods - glad not to have to find a hairdryer!"..."
"First striking the back at a 45 degree angle, and then when we just put it in hot water, a plop sound came and I took it out and opened the lid."..."
"The toughest jar I've ever tried to open! Tried every method I know before resorting to the internet and finding the wooden table spoon method!"..."
Claire Muir
"I loved how if one thing didn't work, you just went on to the next. It almost (almost) stopped the fun when it finally worked."..."
Frances Godfrey
"I got the stubborn lid off a jar by using a spoon.
Thanks for your help."
Rated this article:
Katie Rebecca Wilson
"The hot water one worked on a jar I have been struggling with for days!"
"Never would have thought of using a hair dryer. Great concept!"
Jenny Walters
"The spoon method works like a charm. Will always remember it!"
Rated this article:
"I used an elastic band, worked perfectly! Thanks for the tip!"
"The rubber band worked so well! No effort whatsoever."
Maggi Levasseur
"Steps one and three helped a lot! Thanks, wikiHowers!"
"Very clear explanation. I'm so glad my jar is open!"
"Thank you, wikiHow! You saved the day once again."
"The different suggestions were good."
Zaid Rahman
"The water hammer technique helped."
Augustas K.
"Jar opened. Mission successful."
"Very clear instructions."
"Hot water is the key!"