问题
单项选择题
The lowest point between two waves is called（）.
A.though
B.tough
C.through
D.trough
答案
参考答案：D
搜题请搜索小程序“爱下问搜题”
The lowest point between two waves is called（）.
A.though
B.tough
C.through
D.trough
参考答案：D