解答高中英语语法问题（写出原因,语法点）

解答高中英语语法问题（写出原因,语法点）
25.First impressions are the most lasting.After all,you never get _____ second chance to make the first impression.
A.a B.the C./ D.another
28.Recently a survey _______ prices of the same products in two different supermarkets has caused heated debate among citizens.
A.compared B.being compared C.compares D.comparing
30.Tom was about to close the windows ______ his attention was caught by a bird in the garden.
A.when B.if C.and D.till
33.Valentine’s Day,______ its equivalent,is now celebrated in many countries around the world.
A.but B.and C.or D.yet
34.William Beebe,one of the first men ______ the depths of the sea in a bathy-sphere,got interested in oceanography because of one book.
A.exploring B.having explored C.to be exploring D.to explore
35.advertisements are of great help,I don't think we should entirely rely on them.
A.Since B.While C.Because D.As
37.—Peter was admitted to a second-class college．
—He ________ a top university,but he was addicted to playing computer games．
A．had entered B．would enter C．must have entered D．could have entered
ADACDBD
38.It was April 29,2010 ______ Prince William and Kate Middleton walked into the palace hall of the wedding ceremony.
A.that B.when C.on which D.where
40.________,I believe,and you will find Tom is very outgoing.
A.Having a talk with the student B.Given a talk with the student
C.One talk with the student D.If you have a talk with the student