As for normal communication, it depends on how far you mean.
For example, a simple daily conversation is like going to the supermarket, as long as you know some English, because even if you don't speak very well, others can probably guess what you want to say, and when you don't understand, most of them can guess what others want to do. Even if you can't, you will learn quickly, because they are all simple words you know, but you just don't know how to say them. You've heard it once, and you'll tell it again next time.
If you take a class, you don't have to go to a language school if you score 80 on TOEFL. It takes about 2 or 3 months to understand everything, but it takes a long time to speak fluent English. I don't know if this can meet your communication standards.
Even if you get full marks, you may not know everything. But what is certain is that people with high language scores adapt quickly. Maybe it takes only half a month for people with a score of 65,438+065,438+00 to adapt and learn to speak fluent English, but it takes months for people with a score of 80 to speak English. And in fact, I personally think that part of it is a logical problem, and the test scores are not a complete measure of the standards that can be communicated. Sometimes there is nothing wrong with the language, but when you describe one thing, you will find the logical differences between the east and the west, which will eventually lead to communication obstacles. So, don't be obsessed with how many points you get to communicate normally. Language is a slow learning process. Of course, learning a language also requires learning the culture and way of thinking of this language country. The best way to learn is to be in a language environment.
However, I personally suggest that although you don't have to learn fluent English to go abroad, you should try your best to lay a solid foundation in English so that you can make rapid progress in the United States. Otherwise, there are so many courses in the United States that it is difficult to lay a good language foundation at the same time.