65.The police always get ready to o__________ people their help. 　　

63. The yellow river is the second　 l__________ river of our country.

64 As he e__________ the sea, he took pictures and videos of many things that people had never seen before.

62. Our teacher always speaks h_________ of us when we make a great progress.　

根据下列句子及所给首字母或汉语注释，写出空缺处各单词的正确形式(每空限写一词)。

61. Put a b_______ in your book, then you can easily find the page you are reading.　　　　　　　　　　　　　　

25. The population of this city __________300000.

A. is　　　 B. are　　 C. has　　 D. have

24.__________ the man is very old, __________ he has never stopped studying.

A. Though, but　 　　B. Though, and　　 C. Though, then　 D. Though, \

23. Could you tell me when ___________?

A. does the train leave　 　　　　B. the train leave　

　　　 C. the train leaves 　　　　　　　D. leaves the train