2016冬令营名单:求助！！！！急！英文高手帮帮忙！！

是单项选择题
19.She didn’t go to the cinema last night, ( ) she had to finish her term paper.
A. as B.if C.till D.though
20.I have found some articles ( )the harmfull effects of drinking.
A.being concerned B. concerned C. to concern D. concerning
21.So loudly ( ) that people could hear it out in the steet.
A. did the students play the music B. the students playing the music
B. the students played the music D . have the students played the music
22.At the international conference,the famous scientist gave an excellent report ( ) on his receent experiment.
A. basing B.based C.to be based D.to base
23.There are so many dresses there that I really don’t know ( ) to choose.
A. whether B.when C.which D.why
24.I think thatAnna is ( ) far the most active member in our group.
A. which B.at C.as D.by
25.I’m sill unable to make myself ( ) in the discussion,which worrise me a lot.
A.to be understood B.understanding C.understood D.understand