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I've noticed that the pronunciations of "picked" gives its sound like "pick" with final sound "d" but for "Crooked" and "Naked" Why do they pronounce them like "Crook-ked" and "Nake-ked"?
How can I know when i must pronounce the word like "picked" and when I must pronounce the word like "Crooked"?
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Perhaps because of the well-known nursery rhyme.
There was a crook-ed man, and he walked a crook-ed mile
He found a crook-ed sixpence, on a crook-ed style
... and so forth.
The metre of the nursery rhyme demands the separation of the syllables, and as many of us were/are exposed to this as small children, perhaps it never occurs to us that crook-ed is really the same word as crooked. After all - how commonly do you come across the word in other contexts?
Adjectives whose first syllable end with a /k/ sound and whose second syllable ends with /ɪd/ are rare but they do exist.
crooked (adj) /krʊkɪd/ a crooked path; All politicians are crooked
naked /'neɪkɪd/
wicked /ˈwɪkɪd/
sacred /ˈseɪkrɪd
However, verbs ending with "k" if they are regular, take "ed" in the simple past and are normally pronounced thus:
crooked (verb) /krʊkt/ He crooked his finger at me
walked /wɔːkt/
talked /tɔːkt/
kicked /kɪkt/
cooked /kʊkt/
asked /ɑːskt/
worked /wɜːkt/
In most cases, I believe it has something to do with the construction of the word.
If the normal form of the word (crook, twist) ends in t or d, the -ed is enunciated (such as wanted or bedded).
All other normal form word endings, however, are not voiced. The -e in the past simple and past participle forms is not enunciated (for example, watched, played, liked).
Crooked, however, seems to be one of English's many exceptions. When used as an adjective, such as
his crooked neck,
the -e in -ed is voiced. Perhaps you can find other exceptions to this rule, but they escape me at the moment.
