prevent是指阻止其他人或事物做某事,搭配是prevent sb./sth.from doing,例如prevent him from selling the house,“阻止他卖房子”
avoid是指自己避免做某事,搭配是avoid doing,例如I have done so to avoid seeing the man.“我这样做是想避免看到那个人”.
crime是名词,意为“罪恶”,没有“防止”的意思.