A:可形成-l价离子
B:从上到下原子半径逐渐减小
C:从上到下原子半径逐渐增大
D:从上到下非金属性逐渐减弱
– Is that man Mr. Green?
– It _____ be him. He has gone to Paris on business.
如图,已知 ∠ABC=∠ABD,要使∆ABC≅∆ABD ,下列所添条件不一定成立的是( )