40.________environmental damage is done,it takes many years for the ecosystem to recover.

A.Even if　　　　 B.If only　　　　　　　 C.While　　　　　 D.Once

39.The cost of living in Glasgow is among the lowestin Britain,________the quality of life is probably one of the highest.

A.since　　　　　 B.when　　　　　　　 C.as　　　　　　　 D.while

38.That was really a splendid evening.It’s years________I enjoyed myself so much.

A.when　　　　 　　B.that　　　　　　　 C.before　　　　　 D.since

37.It wasn’t until nearly a month later________I received the manager’s reply.

A.since　　　　　 B.when　　　　　　　 C.as　　　　　　　 D.that

36.________I accept that he is not perfect,I do actually like the person.

A. While　　　　　 B.Since　　　　　　　 C.Before 　　　　D.Unless

35.-Did you remember to give Mary the money you owed her?

-Yes,I gave it to her________I saw her.

A.while　　　　 B.the moment　　　　　 C.suddenly　　　　 D.once