Many species are in ______ danger of extinction now due to the foolish actions of ______ human race.

He hesitated(犹豫) for a moment before kicking the ball, otherwise he _____the goal.

twelve o’clock, I think I must be offnow” “Oh, reallyI ______ it at all”

He has _______ for two years.. Two years _______ a long time.

How clean your car is!—Thank you. It _____ very often.