1.thanks very much for （invite）us to have dinner.2.the wonderful piece of music is so difficult to (play)3.who was (happy),you or your friend jim?根据括号里里的提示,填入适当形式.请说明原因,
问题描述：
1.thanks very much for （invite）us to have dinner.
2.the wonderful piece of music is so difficult to (play)
3.who was (happy),you or your friend jim?
根据括号里里的提示,填入适当形式.请说明原因,
答
1.inviting（for是介词,后面要加doing形式）
2.play(to do不定式做目的状语）
3.happier（形容词比较级,you or your friend Jim是两者比较,要用比较级）