--- Do you know Uncle Tom is crazy about gardening? ---Sure. He ____ his flowers in the garden now.
—What shall we do tonight then? —_______ -whatever you want.
It suddenly occurred to him ________ he had left his keys in the office.
It was a real race ________ time to get the project done. Luckily, we made it.
—How far can you run without stopping? —_________. I’ve never tried.
A serious study of physics is impossible ________ some knowledge of mathematics.