The black box is a necessary device on an airplane, which records its speed, direction and whether everything on the airplane_____normally.[ ]

Watch out ______ cars when you cross the road

If George keeps on working so hard, he’ll ______ sooner or later.

Every minute about ____ babies are born in theword, so the world’s population is increasing by _____million every year.

Tom, put the keys on the table ______ I can remember to take them with me when I go out.