1) prevent to阻止去做某事,表示动作还未发生;prevent from 从某事中阻止,表示动作已经或正在发生
2)prevent to有两种,一种是prevent to do sth,如:
Do not water in before making a turn every time 9 days, make wilting of its branch appreciably, make branch the turn slowly next, prevent to break off or cause " dead turn " . 在每次作弯前一两天不要浇水,使其枝条略微萎蔫,然后将枝条慢慢作弯,防止折断或造成“死弯”。
另外一种结构是:prevent sth. to sth,这里to是介词。如:how to prevent damage to water mains 如何防止损毁水管
3) prevent sth from happening,例如I don't know of anything to prevent you from doing so.我不知道有什么能阻止你这样做。