Class begins()nine o'clock.It is over()quarter()twelve.Lunch begins()twelve.They are talking()some Americans()a map()ChinaI am not listening()music.I am working() the computer填适当的介词

Class begins()nine o'clock.It is over()quarter()twelve.Lunch begins()twelve.They are talking()some Americans()a map()ChinaI am not listening()music.I am working() the computer填适当的介词
Class begins()nine o'clock.It is over()quarter()twelve.Lunch begins()twelve.
They are talking()some Americans()a map()China
I am not listening()music.I am working() the computer
填适当的介词

Class begins()nine o'clock.It is over()quarter()twelve.Lunch begins()twelve.They are talking()some Americans()a map()ChinaI am not listening()music.I am working() the computer填适当的介词
Class begins (at) nine o'clock.It is over (at) quarter (to) twelve.Lunch begins (at) twelve.
They are talking (with) some Americans (about) a map (of) China.
I am not listening (to) music.I am working (on) the computer.

Class begins(at)nine o'clock.It is over(at)quarter(to)twelve.Lunch begins(at)twelve.
They are talking(about)some Americans(for)a map(of)China
I am not listening(to）music.I am working(on) the computer
自己想的 错的还请指教~~~

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