Why is the verb "to hear" an irregular verb, when one has to add a "d" in the past tense, like many regular verbs ?
If the present form of a regular verb ends in -e, we add -d to form the past tense:
He moved into his new house yesterday. (Present form of verb: move)
If the present form of a regular verb ends in a letter other than -e, we usually add -ed to form the past tense:
I visited my friends last evening. (present form visit)
So 'hear' should have been 'heared'