i before e except after c

Remember: it's "i" before "e" except after "c". Simple!

Oh yeah…

That covers it. Oh wait…

If it's a long "e" sound, use "ie" as normal. And if it does not make a long "e" sound, use "ei", like in "heir", "their", "heifer", "weir", "forfeit", "feisty", "gneiss", "height", "heist", and "seismic".

… Except for "neither", "either", "seizure", and "leisure".

And "protein", "seize", "caffeine".

And "keister".

And "species" and "weird".

And "friend". And "mischief".

And none of this applies to words in which "ie" or "ei" are pronounced apart (not a digraph), like "deity", "science", "conscience", "society", and "omniscient".

Oh…

Oh, and it doesn't apply when "ie" is part of the plural form of words which end in "cy", like "policies".

Or a proper noun.

Or if it is a foreign word (or the word "foreign").

Or if it's Tuesday afternoon.

Now, memorize it, and go forth!