—Why did Mr. Green take his 7th grade students to the river yesterday afternoon?—________ the river.
This is ______ difficult problem that few students can work it out.
A notice was ________ in order to remind the students of the changed lecture time.
This is not a match. We’re playing chess just for ______.
They made the longest sofa in the world. It is ten times ______ the ordinary ones.
He is looking forward to ______ what is happening over there.