Reading history books can not only improve our 　　　　　 (知识) of the past but also make us think.
The elderly should be spoken to 　　　　　 (礼貌地).
Deaf people can 　　　　　 (交流) with each other with sign language.
I haven’t been to that island 　　　　　 (也).
The box is 　　　　　 (空的). You can keep your books in it.
B. 用所给单词的适当形式填空。
He wrote the answers too 　　　　　 (care) and made many mistakes.
Our health will 　　　　　 (harm) if we go jogging on smoggy days.
It is my 　　　　　 (please) to volunteer for the show.
Two 　　　　　 (Canada) joined us in the English corner.
An 　　　　　 (operate) was performed in time and the boy was saved.