问题
选择题
Yaoming is really busy. He seldom spends weekends______ his family. [ ]
A. on
B. about
C. in
D. with
答案
答案：D
搜题请搜索小程序“爱下问搜题”
Yaoming is really busy. He seldom spends weekends______ his family. [ ]
A. on
B. about
C. in
D. with
答案：D
sin100πt V，氖泡在两端电压达到100V时开始发光。下列说法中正确的有