stop.from(doing) sth=prevent.from(doing) sth=keep.from(doing) sth但stop和prevent后面的from可省略为什么keep后面的from不可省?
问题描述：
stop.from(doing) sth=prevent.from(doing) sth=keep.from(doing) sth
但stop和prevent后面的from可省略
为什么keep后面的from不可省?
答
keep后面from省略后就变成另外一个意思，只有在keep from doing sth 时才有阻止做某事的意思，而keep doing sth 就是一直做某事的意思，所以keep后面from不可省略。
答
因为如果keep sb from doing sth......省掉之后变成keep sb doing sth意思变为“使某人一直做某事”。所以不能省
答
因为 stop sb.(from) doing sth 和 prevent sb (from) doing sth 省掉了from 不会影响语义,而 keep sb.from doing sth 省掉from后,意思正好相反：I kept him working on his homework —— 我一直让他做作业I kept h...
答
keep doing 表示一直在做，加了from 才能表示prevent的意思