649._______ the project as planned,we'll have to work two more hours a day.
A.Completing
B.Complete
C.Completed
D.To complete
650.Susan wanted to be independent of her parents.She tried ________ alone,but she didn't like it and moved back home.
A.living
B.to live
C.to be living
D.having lived
649.答案是D;根据句意，此处用动词不定式作状语，表示目的。
650.答案是A;注意:try doing sth.试着做某事，而try to do sth.尽力做某事。
