问题
选择题
We all agree that _______ good knowledge of physics is a must in explaining such _______ natural phenomena.
A．a; /
B．a; a
C．/; a
D．/; /
答案
答案：A
搜题请搜索小程序“爱下问搜题”
We all agree that _______ good knowledge of physics is a must in explaining such _______ natural phenomena.
A．a; /
B．a; a
C．/; a
D．/; /
答案：A
