/A/ versus /U/: 34 pairs

bark book
barked booked
Barking booking
barks books
barley bully
card could
fart foot
farted footed
farting footing
farts foots
guard good 
guards goods 
hard hood
hark hook
harked hooked
harking hooking
harks hooks
khaki cookie 
lakh look
lakhs looks
larked looked
larking looking
nark nook
narks nooks
parches putsches
pardon pudden
pardons puddens
parley pulley
parleys pulleys
parts puts
pashas pushers
shard should
shark shook
starred stood