—Do you know the Water Cube at all?—No, this is the first time I ________ here.
Either you or one of your students ______ to attend the meeting that is due tomorrow.
You and I could hardly work together, _____ ?
Please do me a favor — ______ my friend Mr. Smith to Youth Theater at 7:30 tonight.
— It’s the office! So you ______know eating is not allowed here. — Oh, sorry.
Nowadays people sometimes separate their waste to make it easier for it ______. .