题干
It's a good idea________ too much food at night.
A：eating
B：to eat
C：not to eat
D：not eating
答案(点此获取答案解析）
C
It's a good idea________ too much food at night.
A：eating
B：to eat
C：not to eat
D：not eating
轴的正方向在弹性绳上传播，振源的周期为0.4s，波的振幅为0.4m，在
时刻的波形如图所示：则在