题目内容：

帮我这英语白痴
(　　)21.Mr.Smith is one of the foreign experts who ______ in China.
A.works B.is working
C.are working D.has been working
(　　)22.Didn't you see the man ______?
A.I nodded just now
B.whom I nodded just now
C.I nodded to him just now
D.I nodded to just now
(　　)23.In the dark street,there wasn't a single person ______ she could turn for help.
A.that　 B.who
C.from whom D.to whom
(　　)24.Can you lend me the novel ______ the other day?
A.that you talked
B.you talked about it
C.which you talked with
D.you talked about
(　　)25.The matter ______ you were arguing about last night has been settled.
A.that B.what
C.why D.for which
(　　)26.They talked for about an hour of things and persons ______ they remembered in the school.
A.which　 B.that
C.who D.whom
(　　)27.Is there anything ______ to you?
A.that is belonged B.that belongs
C.that belong D.which belongs
(　　)28.His parents wouldn't let him marry anyone ______ family was poor.
A.that B.which
C.who's D.whose
(　　)29.He is the only one of the boys who ______ the piano well.
A.plays B.play
C.playing D.are playing
(　　)30.Stephen Hawking believes that earth is unlikely to be the only planet ______ life has developed gradually.
A.that B.where
C.which D.whose