选的D,用explaining来做前面clause的modifier,表示因为这个用火做饭追溯到200万年前的事,解释了远古人头大牙小;而且fire (used to cook)表示fire date back 200million years,火一直都在,是用火做饭的事追溯到200年前
B:解释的是用火做饭的是追溯到200年前,用火做饭的事也解释了远古人头大牙小,他们两个是独立事件,parallel而已
选的C,现在看来发现答案C提到了上一个recession的时间,无关比较,跟将来的recession period无关
这道题的conclusion是:in the future,when recession happened,teachers in public school wont‘ lose their job。
P:因为政府颁布的政策,公立学校要免费对孩子开放,不管经济,不能超过现在的师生比例
答案B:讲的现在读私立学校的孩子有20%多,但当recession来临,家长交不了substantial的学费,就会去public school,为了保证师生率不变,学校还有再招老师!!!
When it is used in this way in writing, however, it must be used at the beginning of a sentence or at the beginning of an independent clause, and be set off by the use of commas. In any case, the use of hopefully in this sentence is incorrect: in a technical sense, it implies that the enabling of the astronomers will be hopeful.
从题目可得100a + 10b + c - (100c + 10b + a) = 99*(a - c) 要能被7整除——因为99不是7的倍数,所以只能是a-c是7的倍数即=7——注意!!题中规定abc都为非零数字,所以a,c只能是(9,2)和(8,1) ——所以P(abc)=2*9*1=18