Everyone here will thank the firefighter for the things they have done to prevent fires______ the environment safer.
| A．make | B．to making | C．to make | D．from making |
I’m told that languagepractising.com is a free website _____ learners can not just learn various
languages but also chat online.
| A．where | B．which | C．that | D．what |
Either you or any of your family ______ to attend the important banquet that is due tomorrow.
| A．are | B．can | C．have | D．is |
Tom,you and I could hardly work out the mathematic problem, _______?
| A．could you | B．couldn’t I | C．couldn’t we | D．could we |
Even many years after his divorce, he still couldn’t figure out the reason for his ____ marriage.
| A．to fail | B．to be failing | C．failing | D．failed |
— Has Mr. Tom White arrived?
— Yes, already. _____ he wait outside or just come in?
| A．Shall | B．May | C．Could | D．Must |