Is there an easy way to remember when to use ㅐ vs. ㅔ?

Question

Okay, I did see When to use ㅐ, ㅒ as opposed to ㅔ,ㅖ? . But as of today that discussion is only about pronunciation, analogous situations in English, and history. On the problem of how to tell which, someone there just says, you just have to know. Which I get because most people learning the language would be seeing the words as they learn. But for me, I learned as a child just listening and speaking to my parents. So I know how to say things, but I don't have any sense for what words are supposed to look like. I'm trying to text my mother in Korean these days and ㅐ vs. ㅔ is most frequently what slows me down.

So I'm wondering if there are—or anyone here's come up with—a mnemonic or trick to know which to use: ㅐ or ㅔ. Or if someone's up for a challenge and can come up with one :) It would be nice if the trick worked for ㅒ and ㅖ too but I'll take what I can get.

Answer 1

"애" and "에" are often pronounced the same these days in every day usage, but historically were more distinct, with "애" having a more open-mouthed position and "에" a more narrow one (source: TTMIK). But Native Koreans I've spoken to have referred to a "feeling" about which one to use when, but that "feeling" can be wrong for them, too! As far as I've noticed while studying Korean, it's largely memorization unfortunately.

There are however two possibly useful tidbits to help you out:

1. English loanwords tend to use "에" for the [eː] sounding words, often but not always ones that use "e" (think 게임, 인터넷, etc) and "애" for [ɛ] sounding words, often but not always ones that use "a" (think 애플, 샌드위치).
2. Sino-Korean words tend to use "애" more frequently but it isn't a rule (think 매일, 행동).