In this article we will explore commonly confused words including homonyms (word pairs that sound the same but have different meanings).
1. accept / except
Accept is a verb meaning to agree to receive something; except is a conjunction meaning not included.
2. bad / badly
Bad is an adjective; badly is an adverb. Bad will often be used to describe a feeling; badly describes an action.
3. can / may
Can refers to ability; may refers to permission.
4. good / well
Good is an adjective; well is an adverb, and can also be used to mean health.
5. it’s / its
It’s is a contraction of it is; its is a possessive pronoun showing ownership.
6. less / fewer
Use less for quantity measurement that cannot be counted; use fewer for things that can be counted (units).
7. than / then
Than is used for comparisons; then denotes time of occurrence.
8. there / their / they’re
There is an adverb stating where; their is a possessive pronoun showing ownership; they’re is a contraction of they are.
9. shall / will
Use shall with first person and will with second and third persons to indicate the future tense; reverse this to indicate determination or need. (This distinction is being ignored with growing frequency.)
10. your / you’re
Your is a possessive pronoun; you’re is a contraction of you are.
Source: The Essential Handbook For Business Writing by Desmond A. Gilling