你想知道盒子里装的是什么,你会问:________A.Who's that? B.Who's this?C.What's in the box?
What were you doing? I ____ digging a hole. A.was B.were C.am
Wake up, Tony.It’s time _____school. A.to go B for C.go to
You can go when the traffic light is_______. A.yellow B.red C.green
I helped the boy______ the boxes yesterday. A.carried B.carry C.carrying
There _____ a lot of food on the table. A.is B.are C.be