“Underground” is the only word in the English language ____ begins and ends with the letters “und.”
There are about ________ students in our school.
—Do you like our English teacher? —Yes. I think his class is very ________.
This is your pencil. ________ is over there, on the desk.
Doing morning exercises is good ________ our health.
He is going to study hard at math. He wants to be ________ engineer.