【小题1】Reading history books can not only improve our 　　　　　 (知识) of the past but also make us think.
【小题2】The elderly should be spoken to 　　　　　 (礼貌地).
【小题3】Deaf people can 　　　　　 (交流) with each other with sign language.
【小题4】I haven’t been to that island 　　　　　 (也).
【小题5】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。
【小题6】 He wrote the answers too 　　　　　 (care) and made many mistakes.
【小题7】Our health will 　　　　　 (harm) if we go jogging on smoggy days.
【小题8】It is my 　　　　　 (please) to volunteer for the show.
【小题9】Two 　　　　　 (Canada) joined us in the English corner.
【小题10】An 　　　　　 (operate) was performed in time and the boy was saved.

Old people should ________politely.

Old people must __________.