In public places, could you please pay [ə'tenʃn] to your behavior?
A:attention
B:achieve
C:astronaut
D:airplane
下列化学用语书写正确的是 ( )
I haven't seen my grandma for a long time. I can't help her very much.
下面是一个正方体,用一个平面去截这个正方体截面形状不可能为下图中的( )
下列唐朝与国外友好交往的史事,发生在唐玄宗时期的是( )