There are only 20 words that are written with Mai Muan. It
is worth the effort to get to this list from memory. Words
with an "ai" sound, which appear not in this list,
therefore, are written always with the other ai, the Mai Malai.
I'm not a native English speaker and my English is poor.
I've translated this page from my German site because it can be helpful
for Thai students everywhere in the world.