Many etymologically related pairs of words are pronounced differently.
eɪ |
æ |
grade |
graduation |
grateful |
gratitude |
nation |
national |
nature |
natural |
sane |
sanity |
state |
static |
volcano |
volcanic |
iː |
e |
athlete |
athletic |
austere |
austerity |
brief |
brevity |
meter |
metric |
receive |
reception |
sincere |
sincerity |
supreme |
supremacy |
əʊ |
ɒ |
diagnosis |
diagnostic |
holy |
holiday |
know |
knowledge |
microscope |
microscopic |
mode |
modular |
provoke |
provocative |
verbose |
verbosity |
aɪ |
ɪ |
Bible |
Biblical |
collide |
collision |
crime |
criminal |
decide |
decision |
line |
linear |
sign |
signature |
type |
typical |