用括号内所给动词的正确形式填空。
1. Harry Potter is a film that is worth ________ (see) several times.
2. If we don't do anything, the changes ________ (not take) place.
3. When ________ UNICEF ________ (set) up to help governments and families make
the world a better place for children?
4. Sandy ________ (choose) a tie for her father when she travelled in Shanghai.
5. The story was funny enough ________ (make) all of us laugh.
6. So far, a number of doctors ________ (send) to help the sick people in that area.