How do I make vocabulary flashcards for words that have conjugations or are subject to sound rules?

A study with children found that practicing recalling a new verb helped them remember the verb itself, but that benefit did not automatically carry over to correctly adding a grammatical ending (like '-ing') to that same verb the first time they needed to.⁶

Research on German verbs suggests that even when a word's pronunciation shifts across its different inflected forms (due to vowel changes), speakers still access these forms through a single, underlying stored version of the word rather than needing a separate stored entry for every sound variant.³

A classroom study found that teaching methods which explicitly draw attention to a new word's sound form (not just its meaning) led to significant vocabulary gains, and that mastering the correspondence between sounds and spelling was a significant factor in successful word learning.⁹

In a study of Russian noun endings, children who heard novel nouns in more than one form (both a plain and a diminutive version) made fewer case-marking errors than children who only heard one fixed form — suggesting that seeing a word's variants together, rather than always in isolation, can support learning the underlying pattern.¹¹

Comparing flashcard study spread out with a one-day gap versus crammed all at once, spaced-out practice produced better retention two weeks later, even though at first (in an immediate test) there was no significant advantage for spacing.¹

A broad review of word-card (flashcard) research found that studies more often showed larger learning effects for ready-made cards than self-made ones, and recommended that learners make their own cards mainly for new words they encounter naturally, while using ready-made sets for structured review; a separate children's study likewise found a word-based learning method outperformed a picture-based one.^2,5

In an experiment where English speakers learned to inflect Russian nouns, only learners with above-average scores on a general reasoning test benefited from being trained on a larger variety of vocabulary before they could generalize the inflection pattern to new words — for others, more variety didn't help.⁴

Adult second-language learners tend to store new words with less precise, blurrier mental representations than native speakers do, especially for the word's sound/spelling form, and this fuzziness is worse for less frequent words — which would include many conjugated or sound-changed variants that show up less often than the base form.¹⁰

An observational study of an online Korean-learning community found that vocabulary and pronunciation questions (alongside grammar) were among the most common things learners asked about, suggesting these are recurring sticking points for Korean learners generally, though the study did not specifically examine flashcard design.⁸

Research on how foreign words get adapted into Korean shows that Korean speakers apply consistent, rule-governed sound changes when borrowing words, reflecting that Korean's sound system follows describable patterns rather than being arbitrary.⁷

Should I make my own flashcards or use a pre-made deck for tricky conjugated words?

A large research synthesis on flashcard (word card) studies found that, across the studies reviewed, ready-made cards showed larger learning effects more often than self-made ones, and recommended learners mainly self-construct cards for words they encounter naturally and unexpectedly, while relying on ready-made sets for more structured review. This suggests that for systematically working through Korean conjugation patterns, a well-designed ready-made deck (or one built carefully in advance rather than on the fly) may serve you better than improvised cards, though the sources didn't test this specifically for conjugated forms.