第8题: [单项选择]Mr. Goa ______the proposal before he looked at the guidelines. A. (A) writes B. (B) had written C. (C) has written D. (D) will write 参考答案:B 答案解析:An action that is completed before another past action uses the past perfect tense. Choice (A) is th
第10题: [单项选择]A. His vacation has been postponed. B. He needs to take his medicine on vacation. C. He is going to change his allergy medicine. D. His allergy will no longer bother him. 参考答案:B 答案解析:[听力原文] W: Aren’t you leaving tomorrow for vacation Have you got all the things packed and ready
第27题: [单项选择]以下说法哪项错误 A. 多数甾体化合物在环系碳原子的第10、 13位上各有一个甲基，第17位上有个羟基 B. “甾”字中的“田”字代表四个环，“＜＜＜”代表上面的三个侧链 C. 孕激素含21个碳原子 D. 卵巢组织不能摄取血液循环中的胆固醇作为合成性激素的基础结构 E. 由胆固醇合成的孕烯醇酮是所有甾体激素生物合成的前身物质 参考答案:D 答案解析:卵巢能直接摄取血液循环中的胆固醇，作为合成性激素的基础结构。
