Two, to and too
It’s a classic mistake, think: I went to the bar with two of my friends, then they wanted tacos, too. The real origin of this error, which can instantly make you seem a bit less than educated online, is an unclear understanding of the ways to use the double ‘o’ in ‘too’. It can mean ‘also’, as in the example in the first sentence, or it can mean ‘very/excessively’, as in ‘there are too many confusing words in this language’.
Their, they’re, there
To eliminate confusion, remember to only use the apostrophe when it’s a contraction (combining the two words ‘they’ and ‘are’ into ‘they’re’), advises Kathryn Petras, co-author of The New York Times’ bestseller You’re Saying It Wrong. Another easy trick is the secret ‘i’ in ‘their’ can be a way to remember ownership (as in ‘I own that’) to signify possession, even though ‘their’ is for other people’s possession, as in ‘those are their books’.
Affect vs effect
Everyone has that word that has tripped them up since Year 9 English class, and the affect/effect dilemma is high on the list. The good news is, according to Grammarly, it’s a pretty easy fix: affect almost always acts as a verb, while effect is almost always a noun. There are exceptions of course. The numerous homophones in English (words that sound the same) have always made the language notoriously hard to learn, but native speakers struggle just the same.