((即's))'s and (撇號(即s'))s'?

兩者意思其實一樣~!! 都係指 某人/某東西..嘅..

點解有時會用 's, 有時會用 s' 呢?

通常一般都係會用 's~

例如: That is my uncle's car
那是我叔叔的車

但係如果個字係 -s- 尾嘅, 就會用s'~

例如: this is my kids' favorite toy
這是我孩子們的最愛玩具


另外, 它('s)可以是 has / is 嘅簡寫

例如:
she's reading (= she is reading) 她正在閱讀
she's tidied up her room (she has tidied up her room) 她已經把房間收拾好

希望幫到你~!!

2007-01-26 10:37:41 補充：
唔一定係複數名詞架, 請你睇睇呢段新聞, -Jones' Boast Hasn't Paid Off for Cowboys-http://sfgate.com/cgi-bin/article.cgi?f=/n/a/2007/01/23/sports/s204118S42.DTL佢地都係用s' 架~~

2007-01-26 10:51:02 補充：
為何 vsloy 說:*只有*複數名詞，而且以 s 尾 是例外。但係佢下面又話:If the word ends in an s but is singular, practice varies as to ***whether to add ’s or only an apostrophe.***抄嗰陣冇睇清楚??

Please look at the examples:

The boy's pencil is blue.

These boys' pencils are blue.