That was so serious a matter that I had no choice but ________ the police.a. to call in b. call in c. calling in d. called in
To get _______ thorough understanding of oneself also requires doing oneself ______favor when it's needed.
— I can’t bear the air pollution in this city anymore. It is getting worse and worse. — ________! We’ve never had so many chemical factories before.
We guarantee that all your personal information will be treated ________ and there should be no fear at all of identity theft.
You are not ________ to unemployment benefit if you have never worked.
A great deal of hotel business comes from people travelling not just for holidays but by people travelling ________ their business activities.