...using the Internet.句中是for sb doing sth,补充答:如:It is essential for him to be prepared for this. 有必要让他对此有所准备。3. 能用于it’s adj. for sb to do sth的形容词不多,主要的有bad, bold, clever, common, honest, necessary, nice, normal, pointless, rare, (all) right, rude, sensible, stupid, tactful, thoughtful...