Two-letter word quiz
Reading the list is not the same as knowing it. What decides a game is whether you can tell in a second, with a tile in your hand, that oe plays and ie does not — so this drills exactly that, one pair at a time.
Twenty pairs, half of them real. Decide whether each one is a word you can play.
Why these words
Two-letter words are how you score without a good rack. Laying one tile alongside a word already on the board forms two or three short words at once, each collecting the bonus square underneath — and the plays are available on turns when nothing else is. A player who knows this list scores where a player who does not exchanges tiles.
The decoys are not random letter pairs. They are the ones players believe: ja, ok, po, za and qi all feel like words, and none of them is in this dictionary. Getting those wrong here costs nothing, which is the cheapest place to find out.
Learn the list first
If the round is going badly, the answer is not more rounds — read the complete list once, with the notes on which ones surprise people, and come back. It is 96 words. An afternoon is enough.
A note on dictionaries
Answers come from ENABLE, the public-domain list most English word games are built on. Some games differ at the edges — a few add za and qi, which this list does not carry — so treat a word here as very likely accepted rather than guaranteed.