Ⅰ.单句语法填空
1．It was officially(official)acknowledged that the economy was decreasing.
2．“I didn't mean to upset you，”he said mildly(mild)．
3．He was hit by a falling tree and killed on the spot.
4．Many scientists have been working hard to find ways for people all over the world to be in harmony with nature.
5．The PE teacher stood in the middle of the playground，surrounded(surround)by a group of students.
6．The boy sat in the classroom doing(do) his homework.
