【C2】A．whereB．whenC．thatD．which

【C6】A．whereB．whichC．thatD．as

There were dirty marks on her trousers ______ she had wiped her hands.A．whereB．whenC．thatD

I doubt____________he will lend you the book.A.whetherB.whenC.thatD.which

Air is to men______water is to fish.A．whatB．whenC．thatD．which

【C10】A．whileB．whenC．thatD．which

【C3】A．whereB．whenC．whatD．who