1、卵细胞的形成过程中，卵原细胞、初级卵母细胞、次级卵母细胞、卵细胞的个数比是

Ａ．１：１：２：４　　　　　　　　 Ｂ．１：１：１：２

Ｃ．１：１：４：４　　　　　　　　  D．１：１：１：１

36、An average of 130,000 Chinese ____ abroad for studies every year over the past few years, improving exchanges in the educational fields.

     A. was going                                       B. have been going  

     C. has been going                                 D. are going

35、Students in this school don’t have classes on Wednesday afternoon, which is ____ , for teachers have a meeting.

     A. practice         B. action            C. experience      D. sense

34、Were all the passengers on the bus injured in the accident?

--No, ____ only the four who got hurt.

     A. there was       B. there were       C. that was                 D. it was

33、How long do you suppose it will be ____ he arrives at the small village?

--Five hours or so.

     A. when                   B. before            C. since              D. after

32、 Having been praised by the teacher, the little girl ran back home,____.

    A. happily and satisfied                  B. eager and excitedly                     

    C. happy and satisfied                   D. anxiously and excitedly

31、― Do you think he would have given you a hand in your time of financial difficulty?

― He ______ if he had known about it. We are very good friends.

A. must have         B. can’t have                C. wouldn’t have           D. should have

30、______some English-learning websites if you are free, and you will learn a lot about how to study English.

A. Having visited              B. To visit                  C. Visit                      D. Visiting

29、If we know about what causes endangerment, we may be able to takes measures______ it is too late.

A. until                  B. unless                      C. when                       D. before