The big earthquake is reported to have ____ more than 4,000 people homeless. A. remained B. had C. brought D. left 答案:D 解析: 动词leave可用作使役动词,意为“使某人或某物处于某种状态”。
A、B、C均为短周期元素,A、B同周期,A、C的最低价离子分别为A2-和C-,B2+和C-具有相同的电子层结构,下列说法中正确的是
A.
原子序数:A>B>C
B.
原子半径:A>B>C
C.
离子半径:A2->C->B2+
D.
原子核外最外层电子数:A>C>B