—Have you found your lost camera? —No, I haven’t found _____, but I bought _____ this morning． 

I’m moving to the countryside because the air there is much fresher than ________ in the city.

Can you show me ____ pen?   This one is too expensive.

–What did your parents think about your decision?–They always let me do _______ I think I should.

— Is your father or mother a teachers? —            . My father is a doctor and my mother is an office worker.