___ there are living creatures in the outer space as those on Earth hasn’t been proved until now.
| A．How | B．When | C．Where | D．Whether |
Mike is handsome, kind and full of energy. , I can’t speak too highly of him.
| A．As a result | B．By the way | C．In a word | D．On the contrary |
The public transportation in this city is very convenient, where many buses run ______.
| A．occasionally | B．approximately | C．immediately | D．frequently |
—Where have you been all day?
—I _______ some former classmates and I couldn’t get back until it was dark.
| A．have met | B．would meet | C．met | D．had met |
—He is eager to try something he has never tried before.
—Oh, I see. That’s _______ he’s different from others.
| A．when | B．what | C．how | D．where |
As your teacher, I could not have you ______ away with cheating in the exam.
| A．get | B．getting | C．breaking | D．break |