Clearly, in a system _________ every decision is made on the basis of tradition alone, it may be difficult to achieve progress.

My sister ________ for long when she fell seriouslyill

．Mike didn’t notice Alice entering his roomHe __________ a phone call

The plan was so shallow and impractical that noserious _______ was ever made to realize it

If it ________ tomorrow, we won’t go on a trip to the Wild Animal Park.