This will prevent any gas from coming out of the tank.这句话怎么理解

问题描述:

This will prevent any gas from coming out of the tank.这句话怎么理解
1.This will prevent any gas from coming out of the tank.
2.Protecting their children from the knowledge.
3.Parents should judge what their children have done as it is.
第一句和第二句中的from是什么意思?
第三句中 their children have done as it is.

第一句和第二句中的from,是和前面的动词prevent或Protecting 构成词组:prevent sb. from doing sth. 阻止/防止某人做某事protect sb. from sth./doing sth. 保护某人免遭./避免某人做某事 第一句句意: 这将防止汽油...