Common errors

This starts my collection of common errors of words mixed up by many of my students in their writing:

respond (verb) vs response (noun)
WRONG:  I had no respond from my father when I asked him for permission to go out.
CORRECT:  I had no response from my father when I asked him for permission to go out.

advise (verb) vs advice (noun)
WRONG: Father adviced me to study hard for the upcoming examinations.
CORRECT: Father advised me to study hard for the upcoming examinations.

save (verb) vs safe (noun)
WRONG: I tried to safe my neighbour whose house was on fire.
CORRECT: I tried to save my neighbour whose house was on fire.

relieve (verb) vs relief (noun)
WRONG: I heaved a great sigh of relieve when he got down safe.
CORRECT: I heaved a great sigh of relief when he got down safe.

letter vs alphabet
WRONG: 'A' is an alphabet.
CORRECT: 'A' is a letter in the alphabet.

horn is a noun, not a verb!
WRONG: Father horned at the inconsiderate driver who changed lanes suddenly.
CORRECT: Father sounded his horn at the inconsiderate driver who changed lanes suddenly.

Commonly mis-spelt words:
embarrassed; referred vs offered; stifle a yawn, immediately, curiosity (no 'u' after 'o'), continuous, refrigerator (no 'd')