Nuclear science should be developed to benefit the people _____ harm them.

If you are invited to any special occasion such as a wedding or a celebration, you’ll have to be ____ dressed.

Last night Mr. Crook didn’t come back at the usual time. ______，he met some friends and stayed out until midnight.

---- Hi, Mark. How was the musical evening? ----- Excellent! Ales and Andy performed _________ and they won the firs prize.

Jack knows _____ little English that he has never found an _____ job.