(     )21． The three letters are all _______ ．

根据提示写一封60词左右的信。

Tom邀请Li Ping参加他这个周日的生日宴会，但Li Ping的父母出差要到下个月才能回来，奶奶又卧病在床，需要人照顾。而且英语考试即将来临，因此，无法前去参加Tom的生日宴会。Li Ping感到很抱歉，只好写信辞谢。

Dear Tom，Thank you very much for inviting me to your birthday party． I-d love to go but I can-t． My

parents．

5． Why don't you go skating today?（改为同义句）

______ ______go skating today?

44． Ben has to study for the English test．（改为否定句）

Ben ______ ______ ______study for the English test．

42． I’m sorry that I am late．（改为同义句）

I’m sorry______ ______ ______ ．

43．1 have to go to the doctor．（对划线部分提问）

_______ ______you have to______?

40． We are not _f______ ，but very busy now．

41．—Would you love to play football with us?（作肯定回答）

—Yes，______ ______ ______ ______．

39． Tom_ i ______Mary to his birthday party yesterday．

37． With _w ______were you talking when I came in?

38． We have to go to school at 7:00 am on w   ．