Mary ________ a math problem with her classmates when the math teacher knocked at the door.
A.has discussed B.discussed C.was discussing D.discusses
Johnson likes to take down what happens every day in his diary. This ________ a habit of his.
A.had been B.was C.has been D.will be
With the development of science and technology, robot ________ in our families.
A.appear B.appeared C.will appear D.are appearing
Just a minute, Mom. I ________ a phone call. I'll take out the rubbish later.
A.answered B.answer C.am answering D.will answer
The twins didn’t go to the theatre, they ______ the light music all night.
A.have enjoyed B.will enjoy C.are enjoying D.were enjoying
Don’t return the video to Peter, I _____ it.
A.don’t watch B.won’t watch C.haven’t watch D.wasn’t watching
