[文法重點]

Perfect Modal Verbs (情態動詞 + have...

[文法重點]

Perfect Modal Verbs (情態動詞 + have + p.p.)

Many of you have trouble using perfect modal verbs on the TOEFL and IELTS so here is an explanation!

Additional Information:
may and might: http://oxforddictionaries.com/words/may-or-might
http://jessielinhuiching.wordpress.com/2012/03/20/情態動詞的過去式-past-modals/
http://beike.dangzhi.com/view/8yy80m

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