I.用适当语法形式或词汇填空。从A、B、C和D四个选项中选出一个最佳答案，写在
答题纸相应的位置上。(本大题共20小题，每小题1分，共20分)
1. I got to the airport only to find that the plane had left______.
A. for ten minutes B. since ten minutes ago
C. ten minutes D. ten minutes before
2. The committee for local development asked that the highway______ alongside the railway.
A. be built B. must build
C. should build D. will be built
3. John worked for more than ten years in a high school ______ the university.
A. attach to B. be attached to
C. attached to D. attaching to
4. Scarcely had Mary closed the door ______ heard the telephone ring.
A. when B. after
C. then D. i
5. I have always regretted ______ studied harder at school.
A. not to have B. not having
C. to have not D. having not
6. Tom, ______ he had done, could at first say nothing.
A. horrified by that B. horrifying by that
C. horrified by what D. horrifying by what