霍乱毒素每个毒素分子含有1个A亚单位和几个B单位()
A.1~3
B.2~4
C.3~5
D.5~7
E.4~6
参考答案:E
—I'm sorry I forgot to post the letter for you.
—_____. I'll post it myself, then. [ ]
A. Don't
B. That's OK
C. Take it easy
D. It's too bad
一则新闻“ 预计部分省份明年一季度可以实施‘单独’家庭生二胎政策”成为社会近期热议的话题。小华的爸爸说:“现在计划生育已经不再是我国的基本国策。”
判断:___________
理由:
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