By looking at a problem in as many ways as possible, creative thinkers can find solutions that would ___ remain invisible.
A. otherwise B. yet C. already D. forever
It was foolish of you to take a taxi ___ you could easily walk there in five minutes.
A. while B. when C. since D. before
He is only too ready to help others, seldom, ____ refusing them when they turn to him.
A. if never B. if ever C. if not D. if no
The traditional approach ____ with complex problems is to break them down into smaller, more easily managed problems.
A. to dealing B. in dealing C. dealing D. to deal
Someone called me up in the middle of the night, but he hung up ____ I could answer the phone.
A. as B. since C. before D. until
------ What made little Tony so unhappy and cry in his room?
------- _________to go biking with his brother.
A. Having not been allowed B. Not having allowed
C. Having not allowed D. Not having been allowed.
