名词综合练习I. Find the choice that best completes each of the following sentences.1. Last Sunday I saw four _ carrying many bags on their shoulders.A. passer-by B. passer-bys C. passers-by D. passers-bys2. Mary used to have two _.A. boys friends B. boys friend C. boy friend D. boy friends3. Jim and Bob are _.A. my father and mother friends B. my father and mothers friendsC. my fathers and mothers friends D. friends of mine father and mo