Well, you can very often deduce which one it is from cognate words, or general language patterns, so it's not just rote learning. e.g. this random headline fro

Well, you can very often deduce which one it is from cognate words, or general language patterns, so it's not just rote learning. e.g. this random headline from Pravda today: "Байден намерен обсудить поведение России на встрече с Путиным" NAMEREN - obviously a, since NA is a common prefix OBSUDIT' - obviously o, since OB is a common prefix POVEDENIE - obviously o, since PO is a common prefix ROSSII - hopefully you can spell the name of your country... or if you don't know how to spell OPRAVDAT' (justify) which has its stress on the ultimate syllable, you just need to recall the name of the glorious newspaper above, PRAVDA, where the stress is on the first A. or GOROD is easy to spell because -oro- is a very common cluster.