答:分号与逗号很相近,可能是分号误成逗号了.
keep sb.doing sth.是使某人一直做某事.
keep sb.from doing sth.才是阻止某人去做某事.
=prevent /stop sb.from doing sth.
然而后两个中的from以省略,意思不变,这是要注意的.
改:It has been raining for a few days ; we must do something to keep the roof from falling.
译:已经下了好几天的雨了.我们一定要采取措施防止房顶倒塌.