1.I thought you had planned to practice the piano today.I did nothing but____lettersall day.A.write B.to write C.wrote D.writing2.I hear that you and Francis will spend your vacation in Nepal next spring.Yes,we are planning____.A.to B.to be C.it D.to do it我知道这题选A,但是为什么呢?老师好像说过是个不定式的省略问题,谁能给我详细讲讲不定式省略?3.Most of the people ____to the party were famous scientists.A.invited B.to invited C.being invited D.be invited为什么选A不选D?4._____more attention,the trees

1.I thought you had planned to practice the piano today.
I did nothing but____lettersall day.
A.write B.to write C.wrote D.writing
2.I hear that you and Francis will spend your vacation in Nepal next spring.
Yes,we are planning____.
A.to B.to be C.it D.to do it
我知道这题选A,但是为什么呢?老师好像说过是个不定式的省略问题,谁能给我详细讲讲不定式省略?
3.Most of the people ____to the party were famous scientists.
A.invited B.to invited C.being invited D.be invited
为什么选A不选D?
4._____more attention,the trees could have grown better.
A.given B.to give C.giving D.having give
为什么选A?
第一题是选A,会的能讲下原因么?再加一题：
5.Snow was falling when they went along the mountain path________ to the front.
A.to lead B.led C.leading D.being led