She tried hard to keep calm in face of the students, but the sweat on her forehead ______her_______.
By looking at a problem in as many ways as possible, creative thinkers can find solutions that would ___ remain invisible.
It was foolish of you to take a taxi ___ you could easily walk there in five minutes.
He is only too ready to help others, seldom, ____ refusing them when they turn to him.
The traditional approach ____ with complex problems is to break them down into smaller, more easily managed problems.
Someone called me up in the middle of the night, but he hung up ____ I could answer the phone.