sew / so / sow are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
sew: (verb) fasten by sewing; do needlework. (verb) create (clothes) with cloth.
so: (adverb) to a very great extent or degree. (adverb) in a manner that facilitates. (adverb) in such a condition or manner, especially as expressed or implied. (adverb) to a certain unspecified extent or degree. (adverb) in the same way; also. (adverb) (usually followed by `that') to an extent or degree as expressed.
sow: (noun) an adult female hog. (verb) place (seeds) in or on the ground for future growth. (verb) introduce into an environment.
sew: s·OW
so: s·OW
sow: s·AW
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)