— You can't imagine ______ little ants can carry ______ heavy a thing.

— That's what we should learn from ants.

用括号里所给动词的适当形式填空。
(1)He often ____ (study) with his friends in the library after class.
(2)We should do more exercise ____  (keep) healthy.
(3)These magazines must not ____  (take) out of the reading room.
(4)  I called you this morning, but nobody answered it.
     Oh, we ____ (run) in the park.
(5)Jacky Chen ____  (star) in many action films for many years. I admire him very much.