If water becomes increasingly scarce in decades ________，water shortage will become a hot issue all over the world.
A．coming B．having come
C．to come D．to be coming
If there is a lot of work ________， I'm happy to just keep on until it is finished.
A．to do B．to be doing
C．done D．doing
To learn English well, we should find opportunities to hear English ________ as much as we can.
A．speak B．speaking C．spoken D．to speak
A cook will be immediately fired if he was found ________ in kitchen.
A．smoke B．smoking C．to smoke D．smoked
—Excuse me，sir, where is Room 301?
—Just a minute.I'll have Bob ________ you to your room.
A．show B．shows C．to show D．showing
The teacher asked us ________ so much noise.
A．don't make B．not make
C．not making D．not to make
