The old man has three sons，and two _____ are doctors．
A.of which B．of whom C．of them D．of that
"How dare you say that?" The teacher said ___ to Tom.
A. angrily pointed B. and angrily pointing
C. and point angrily D. angrily pointing
We have to keep _______ with the changing times.
A. step B. the pace C. a pace D. pace
---Be careful! Your clothes will catch fire.
---Thank you._______ so close to the fire.
A. I didn’t know I was B. I don’t know I am
C. I hadn’t known I was D. I don’t know I was
He is an hour late by now．He last night．
A．must stay up B．should stay up
C．must have stayed up D．should have stayed up
— I knocked over my coffee cup. It went right over ______ keyboard.
— You shouldn’t put drinks near ______ computer.
A. the; / B. the; a C. a; / D. a; a
