Mum,may I go out to fly kites-Sorry.Please don’t go out___________your work is finished.

With the nuclear crisis worsening in Iran, the world’s attention is fixed again onis called the Middle East.

Joe, my close friend, moved to Beijing years ago, and I ____ him since then.

As is natural, a snake like this _____be very dangerous.

It was with great joy _______ he worked out the problem that he had long been puzzled about.