prevent:
◆ to stop something bad from happening, often before it starts or stop someone from doing something
阻止某件不好的事情发生，往往在其发生之前，或阻止某人做某事
◆ structure(结构):
◆ Prevent something (from happening)
◆ prevent someone from doing something
◆ e.g.
◆ These methods prevent pregnancy.
这些方法可以防止*。
◆Further treatment will prevent cancer from developing.
进一步的治疗可以防止癌症的发展。
◆ His back injury may prevent him from playing in tomorrow’s game.
他背上的伤可能使他无法参加明天的比赛。
avoid:
◆ basically, means to miss something or make something miss you or to stay away from someone or something
错过某事或让某事错过你，或远离某人或某事
◆ structure(结构):
◆ avoid something
◆ avoid doing something or avoid someone
◆ e.g.
◆ You should avoid over-spending in the first half of the year.
上半年，你应该避免过度消费。
◆ She took a different route to work to avoid getting stuck in traffic.
她选了一条不同的路线去上班，以避免堵在路上。
◆ I avoided meeting my ex.
我避免与我的前任见面。
◆ Why did you speak to him? You usually avoid him like the plague.
你为什么和他说话？你平常躲他就像躲瘟疫一样。
How are “prevent” and “avoid” different?
“Prevent” and “avoid”，到底有什么不同呢？
我们再来看几个例子：
◆ I always wear a helmet when I’m cycling. Helmets prevent head injuries. And I always use a security lock to prevent theft.
我骑自行车时总是戴头盔。头盔可以防止头部受伤。而且我使用安全锁来防止偷窃。
◆ Well, I take vitamin C to prevent colds. And vitamin E, that prevents heart attacks and strokes.
我服用维生素C来预防感冒。还有维生素E，可以防止心脏病发作和中风。
◆ A: Let’s go home.
B: But it’s only 4:30.
A: But if we leave now, we’ll avoid rush hour.
B: Oh, good idea.
A：我们回家吧。
B：但现在才4点半。
A：但是如果我们现在离开，就可以避开下班高峰期。
B：哦，好主意。
(We want our journey to be fast, so we’re trying to avoid heavy traffic. We can’t prevent the rush hour, but we can stay away from it or avoid it. When we avoid something, we try not to go near it.)
(我们希望快点回家，所以我们要避开（avoid）繁忙的交通。但我们无法阻止(prevent)高峰期，我们可以远离它或避开它。当我们avoid某些东西时，我们尽量不靠近它）。
◆ Everyone seemed to be avoiding Mike.
每个人似乎都在躲避迈克。
(We might avoid people we don’t like, then we stay away from them.)
(我们可能会避开我们不喜欢的人，所以我们远离他们。)
重点：
1. Prevent is just about stopping something from happening, but Avoid can also mean keeping away from someone or something.
Prevent只能用来形容阻止事情的发生，尤其是在某事发生之前，预先阻止；但Avoid还可以用来形容远离某人或某事。
2. 结构不同：
◆ prevent something (from happening)
◆ prevent someone from doing something
◆ avoid something
◆ avoid doing something or avoid someone
