4. The students started _______ at 10:10 a.m. and finished ________ at 12:00 a.m.(A)singing； practic
問題詳情
4. The students started _______ at 10:10 a.m. and finished ________ at 12:00 a.m. (A)singing； practicing (B) to sing； practiced (C) to sing； to practice (D) sang； practicing