Verbs with coalescence of consonants and vowel shortening
Many verbs derive from Germanic strong verbs, which make many of their inflected forms through vowel gradation, as can be observed in Modern English patterns.
For READ: Past tense and past participle also spelt READ, but pronounced with a short vowel /ɹɛd/.
To find the correct form, you can use an online database of the irregular verbs.
For example: irregular verb READ