when, while & if 有d唔明

when
(用作疑問副詞)什麼時候,何時
I'd like to know when they'll let him out.
我想知道他們什麼時候放他。
while
I'll be back in a while.
我一會兒就回來。

2006-12-05 19:32:36 補充：
你見下個例子when系用在中間，當然佢也都會放在尾部，但系就會少D出現while系用在中間和尾部，這兩個情況系時常出現的，仲有就系佢有時while出現之後ge果D動詞系會加ing Form ge ，兒有時while出現之後佢系會變成"Future Tense"子不過我站時find 唔到比你體我盡量今find比你體 (根住補充返)

2006-12-05 19:34:23 補充：
while的例子同賣一D其他的解釋當...的時候,和...同時She listened closely while he read the letter.他讀信時,她聽得很仔細。I'll take care of your children while you are away.你不在時我會照顧你的孩子的。We must strike while the iron is hot.我們必須打鐵趁熱。

2006-12-05 19:41:03 補充：
有時while出現之後系會加ing Form以下例子:While I am opening the door,a bird flies into my house.當我開門的時候，一隻小鳥飛進我的屋內。While I was talking to John, I was mending my dress.我一面跟John說話，一面縫補我的裙子。

When will you visit me?
While I was working, I heard a loud sound.
If you need me, I'll help you.

if是用在假設句,if…i wi||…如果不能實現:lf I were a cat,i wi||…就用past tense。While不知道。When可以包含很多東西:When I working,the door bell rang.(past continous tense)

when係1後短既時間做既野用ge~
while就係1後時間內做既野用既~
if就係如果~有4種用法~問miss la~唔想打because of too long~
冇1個情況下可以用邊個都無所謂