已知X,Y为短周期元素,两元素形成化合物XY2,已知原子序数分别为a和b,则a不可能为[ ]
A.b+4
B.b-5
C.b+6
D.b+8
答案:A
What he did _____ what he said moved us. [ ]
A. more than
B. rather than
C. less than
D. no more than
写作者运用陈述性的语言,把人物的经历、事件和事物的发展变化过程表达出来的一种方式是()
A.叙述
B.描写
C.说明
D.议论