One letter:
* a (article)
* I (pronoun)
Two letters:
* as (adverb)
* be (verb)
* by (preposition)
* go (verb)
* he (pronoun)
* if (conjunction)
* in (preposition)
* is (verb)
* it (pronoun)
* me (pronoun)
* no (adverb)
* of (preposition)
* on (preposition)
* so (adverb)
* to (preposition/infinitive marker)
* up (adverb/preposition)
* we (pronoun)
* you (pronoun)
Three letters:
* and (conjunction)
* are (verb)
* but (conjunction)
* for (preposition)
* has (verb)
* her (pronoun)
* him (pronoun)
* his (pronoun)
* its (pronoun)
* not (adverb)
* out (adverb/preposition)
* see (verb)
* she (pronoun)
* the (article)
* was (verb)
* who (pronoun)
* why (adverb)
Four letters:
* have (verb)
* here (adverb)
* then (adverb)
* they (pronoun)
* this (pronoun/adjective)
* that (pronoun/adjective)
* what (pronoun/adjective)
* with (preposition)
* your (pronoun)
Five Letters:
* about (preposition/adverb)
This list contains only common words used in everyday English. There are some shorter words that are less common or have specialized meanings.