need表示“需要”时,后接动词的ing形式,用主动形式表示被动意义,相当天to be done.本句可翻译为“汽车需要修理”,从语态的角度理解应当是“汽车需要被修理.”也可以用不定式表示为:It needs to be mended. 类似的还有require,want等.例如: The problem requires discussing.= The problem requires to be discussed. The screen wants cleaning.= The screen wants to be cleaned. 再问: 那need to do sth 呢?