It is widely accepted that young babies learn to do things because certain acts lead to________.

29．—May I speak to your manager at three o’clock tomorrow afternoon ?—I’m sorry, He to Shanghai by then

It’s bad news that quite a few rare animals are ________ each year.

Isn’t that your teacher over there? —No, it ______ be him. I’m sure he doesn’t wear glasses.

Do you know ______ man on TV— Yes, he is _____ honest person. Now he is planning ____ one-day trip.