A:2n,2n,4n,n
B:n,4n,2n,n
C:4n,2n,n,n
D:2n,4n,2n,n
— Did you get up late yesterday morning?
— Yes, so after ________ quick breakfast, I had to run to school.
下列句子中没有语病的一句是( )
如图甲所示,验电器A带负电,B不带电.用带有绝缘手柄的金属棒把验电器A、B两金属球连接起来的瞬间(如图乙所示),金属棒中( )
我国有文字可考的历史从( )开始。