其实 只是两种不同的表达法而已,
The students （who are different in character )are quiet similar in their interests .
这是用定语从句作定语,修饰 The students .
The students （ different in character )are quiet similar in their interests
这个句子只是形容词短语作后置定语,同样也是修饰The students .
表达形式不同,但意思完全一样.