76. How are you going to _______ (证明) that it is difficult for giant pandas to survive in the wild?

75. Fang-fang's mother is busy doing her business, so she isn't able to___________( 留出,匀出) time for her daughter.

74. Like many famous scientists, Yuan Long-ping _____ (致力于) himself to the study of science.

73. Thanks for offering me some suggestions. They will be of great__________(价值) to me.

72. Now, school children all get ____________(免费的) books from the government in China..

A. 根据句意、汉语提示或首字母提示写出单词。

71. Andy is so busy that he hasn’t ____________(回复) my last three e-mails.