发现了“元素周期律”和“元素周期表”的科学家是( )
A.牛顿
B.道尔顿
C.阿伏加德罗
D.门捷列夫
答案:D
简述唐代中日体育的交流。
She ______have stopped her work halfway.
A.ought to not
B.ought not to
C.not ought to
D.does not ought to