Ⅰ.单句语法填空
1．The bell ________(ring), all students rushed into the classroom.
2．Sometimes, we should deal with a problem ________(flexible)．
3．My English teacher always assists me ________my English study.
4．He fell down ，but he picked ________ up quickly and went on.
5．Please stop advertising your product in such a way that may be ________(harm) to our kids.
6．A great deal of water ________(waste) every year, which is not a good thing.
