68. 几年前，因为某种无人知晓的原因，这种稀有的鸟绝迹了。

　 Several years ago a rare species of bird 　　　　　　　　for some unknown reason .

67. 无论他是怎么完成的，这都是一个巨大的成功。

　 No matter how he did it , it was a 　　　　　　　　.

根据所给中文意思完成句子，每空只填一个词。

66. 如果你们有什么问题，请随时举手。

If you have any questions , feel free to 　　　　　　　　your hands .

45. He met many problems 　　　　he was going over his lessons .

A. before　　　 B. as soon as　　　 C. since　　 D. while

44. This is 　　　　I wanted .

A. the one what　　　　 B. which　　　 C. one which　　 D. the one

43. -Can you guess 　　　　the MP4 player yesterday ?

　 　-Sorry , I’ve no idea about it .

A. how much did he pay for　　　　　 B. how can he get

C. how much he paid for　　　　　　　 D. how he has got