22. —Who______ it be that is knocking at the door?
—It ______ be Father, but I’m not sure.
| A．can; must | B．can; may | C．must; can | D．may; must |
At the railway station，the mother waved goodbye to her daughter until the train was________.
| A．out of sight | B．out of reach | C．out of order | D．out of place |
is not yet decided.
| A．Whether he will write the book | B．Whether will he write the book |
| C．If he will write the book | D．If will he write the book |
Along with the letter was his promise _____ he would visit me this coming Christmas.
| A．which | B．that | C．what | D．whether |
The young dancers looked so charming in their beautiful clothes that we took
pictures of them.
| A．many of | B．masses of |
| C．the number of | D．a large amount of |
Social attention should be paid our earth from.
| A． to prevent; being polluted | B． to preventing; polluted |
| C． to prevent; polluting | D． to preventing; being polluted |