Mr. Brown ______ his office an hour ago and he is still on his way home.
| A．left | B．leaves | C．is leaving | D．was leaving |
Scientists study ____ human brains work to make computers.
| A．when | B．how | C．that | D．whether |
I make $2,000 a week, 60 surely won’t make ______ difference to me.
| A．that a big | B．a that big | C．big a that | D．that big a |
He will come to understand your efforts sooner or later. It's just a matter of.
| A． | luck | B． | value | C． | time | D． | fact |
This training program can give you a lift at work,increase your income by 40%.
| A． | as well as | B． | so long as | C． | so much as | D． | as soon as |
In our class there are 46 students,half wear glasses.
| A． | in whom | B． | in them | C． | of whom | D． | of them |