Preserve 表示"保护""维护"（某事物），使之尽量不变。

　　Wax polish preserves wood and leather.上光蜡能保护木头和皮革。

　　【即学即练1】

　　用defend, guard, protect, preserve 的适当形式填空。

　　（1）Every nation keeps their own army with the purpose of their country.

　　（2）The prisoners must be by policemen or they will run away.

　　（3）Do you think if women and children are well .

　　（4）Ice helps to food.

2）【原句】 ... and are more likely to touch them.

　　易混词语辨析：likely, possible, probable

likely:从外表.迹象上看，有可能发生，可以以人也可以以物作主语，常用句型是it's likely that ...或 sb. /sth. be likely to ...。

　　They are likely to come here late. / it's likely that they are coming here late.他们可能会晚到。

　　Possible 强调客观上有可能，但常会有实际希望很小，常用it作主语，不能以人为主语。

　　It's possible for him to win the match today. (it's possible that .../to do...)他很可能今天会赢得比赛。

Probably 语气比possible强，带有大概，很可能的意思，比possible表示的可能性大。用it作主语，不能以人为主语，常用句型it's probable that.../to do...。

　　It's probable that there will be rain tonight.今天晚上可能会下雨。

【即学即练2】

　　用likely, possible, probable填空。

　　（1）They are very to receive your invitation.

　　（2）He decided to build a helicopter, even though many experts said it was not .

　　（3）I should think it very , and you certainly will be successful.