udy of natural history is not something to be left to biologists. In fact, their capacity __________ the time they can spend away from their offices is very limited.

Peter, don’t forget your aunt when you are in Hangzhou.— I won’t, Mom.

h patient, ________ dialogue on an area of disagreement, partners frequently discover common threads to build upon.

I’m _____ in collecting stamps at all.

Miss Gu is _____ teacher. She teaches ____ Chinese.