DonnaYoung.org
Words with ie  and ei:

When the sound is e write ie except after c

Words:

relieve, priest, relief, chieftain, grievous, field, belief, yield, thief, shriek, reprieve, besiege, piece, pierce, cashier, reprieve, brief, sieve

Words after c:

conceit, ceiling, deceive, perceive, receipt, deceit, conceive, 

When the sound is other than e, usually write ei Words:

eight, rein, veil, heir, weight, their, sleigh, vein, neigh, skein, neighbor, reign, freight, heifer, weir, weigh

Exceptions

There are always exceptions.

Words:

friend, mischief, seize, sheik, weird, either, neither, financier, leisure, seize, species,