In a natural disaster, minutes and even seconds of warning can make the between life and death.
.—Have you finished the work?—Not yet. I _______ to do it just a moment ago.
.______ is known to everybody, the moon travels round the earth every month.
.When you are driving on this road, you have to limit your speed _____ 60 miles per hour.
.—What do you mean. There are only ten tickets?—There ______ be twelve.
.Jane is said _______ an opera singer in her youth.