I’ve noticed that some schools list 2 years of a foreign language as part of their admission requirements. Does this mean that I won’t be accepted if I haven’t taken 2 full years of a foreign language at my school? Could proof of language proficiency be enough?
In general, you must fulfill high school foreign language course requirements to be admitted to larger public universities. At smaller private colleges, on the other hand, these specifications tend to be more like guidelines. Smaller schools can afford to review applications on an individual basis and examine any other academic passions that might rightfully demand more of your time than foreign languages. Small private colleges are also autonomous, so their requirements are easily bent to accommodate special cases. Since public universities are connected to state governments, they usually have rules for admission that are based in state law (and thus pretty much set in stone). They typically won't make exceptions for individual students.
For example, at UMASS Amherst, the admissions website states explicitly that you must fulfill all the course requirements to be eligible, which include two years of the same foreign language. There's no way to test out of this requirement, so proficiency won't excuse you from the classes. On the other hand, Yale's admissions website says:
Yale does not have any specific entrance requirements (for example, there is no foreign language requirement for admission to Yale). But we do look for students who have taken a balanced set of the rigorous classes available to them. Generally speaking, you should try to take courses each year in English, science, math, the social sciences, and foreign language.
You'll probably be better off if you take at least a couple years of the same foreign language, but you won't necessarily face rejection if you decide to go a different route. It depends heavily on where you're applying, so I'd recommend consulting the information on the admissions websites for the schools that interest you. If their policy is still unclear to you, you can always contact the admissions office and ask them directly. If at all possible, you should try to take at least two years of foreign language in high school just to be safe!