在光纤中，C波段的波长为（），L波段的波长为（），S波段的波长为（）。
参考答案：1525~1565nm；1570~1620nm；1400nm
In this experiment, they are woken up several times during the night, and asked to report what they＿＿＿＿.
A．had just been dreaming
B．are just dreaming
C．have just been dreaming
D．had just dreamt
He asked his father . [ ]
A. where it happens
B. what was happen
C. how it happened
