protect、keep、prevent、stop句型有什么不同?强人进

有一个办法，查原文字典

protect 保护
keep 保持. (某物静止在某一状态)
prevent 预防 (某事发生)
stop (停止继续做某事)

protect：protect sb.from doing sth.使某人受到保护,免受于…prevent/stop/keep sb. from doing sth.防止某物免受于…keep from 的from可省时,是继续做某事

I don't get the sligtest idea about grammars. I would just give you the following samples.
1.My job is to protect people.
2.I am just trying to keep everybody safe.
3.We shall come tomorrow if nothing prevents.
4.The scientists are doing their best to stop the hurricane from destroying everything.