短周期元素A、B,若A离子与B离子电子层结构相同,且A离子半径大于B离子半径,则下列说法一定正确的是 ( )A.原子半径A<B B.电负性A<BC.元素A、B不同周期 D.A原子序数小于B原子序数
_______ pleasant journey it is!( )
A.HowB.WhatC.What a
My best friend helps to ______ the best in me,as the saying goes.( )
A.bring outB.bring inC.bring up
Artemisinin _______ by Tu Youyou,a great Chinese scientist.( )
A.was inventedB.invented
C.has invented
As our children get bigger,our house seems to get ________.( )
A.the smallerB.smaller
C.smallest
The watch _______ you gave me keeps perfect time.( )
A.whoB.whatC.that