（ ） What are you going to do _______ this afternoon?
| A．in | B．on | C．/ | D．at |
( ) If I ____ you tomorrow, I will give you the receipt.
A. see B. will see C. am seeing
( )—— What day is today —— It's ______.
A. Monday B. a fine day C. September 1st
( ) The students couldn't help ______ when they heard the joke.
A. to laughB. laughC. laughing
( ) Do you know ______ this word?
A. what to spell B. how to spell C. to spell
( ) Be quiet! The babies ________.
A. sleep B. are sleeping C. slept