A number of students ______ playing on the ground but I don't know what the exact number______.
— Let’s go and listen to Mr. Smith’s speech on Western culture, shall we?— ______ It’s getting to the end.
— Kitty, do you know ______?— Sure, about forty minutes.
I can’t find my milk in the fridge now, but there ______ some just now.
— We’ve never ______ astronauts’ life though we’re interested in.— Really? I’ll offer you some books about it.
— Jane. I can't find Mike in the playground.—Oh. He ______ the piano in the music room.