It's a good habit _____ breakfast every day. [ ]
A. had
B. have
C. has
D. to have
答案:D
有红球和绿球若干个,如果按每组1个红球2个绿球分组,绿球恰好够用,但剩5个红球;如果按每组2个红球5个绿球分组,红球恰好够用,但剩5个绿球,则红球和绿球共有( )个。
A.122
B.125
C.130
D.132
单先半自动闭塞区间,出站信号机的开放受()控制。
A.联锁设备
B.列车进路
C.闭塞机
D.信号按钮