637.It's very kind ____ you to repair the bike _____me.
A.for;for
B.of;of
C.of;for
D.for;of
638.The boy is waiting ______ his sister and they will go to the hospital to wait ________ their sick mother.
A.for;on
B.on;for
C.for;for
D.on;on
637.答案是C;
It's very kind of sb.to do sth.固定句型;repair sth.for sb.为某人修某物。
638.答案是A;
wait for sb.等某人;wait on sb.伺候某人。