Common mistakes in English can vary depending on the individual's language background, level of proficiency, and the specific context. However, there are some errors that are frequently observed. Here are some common mistakes in English: 

Misusing “there” “their” and “they’re”

“There” refers to a place.
“Their”is a possessive form.
“They’re” is a contraction for “they are”
Confusing “its” and “it’s”

“Its” is a possessive form.
“It’s” is a contraction for “it is” or “it has”
Mixing up “your” and “you’re”

“Your” is a possessive form.
“You’re” is a contraction for “you are”
Incorrect use of “to” “too” and “two”

“To” is a preposition.
“Too” means also or excessively.
“Two” is the number 2.
Misplacing apostrophes:

Confusing possessive forms with plurals, e.g., “The cat’s are cute” instead of “The cats are cute”
Subject-verb agreement errors:

Ensuring that the subject and verb agree in number, e.g., “He don’t” instead of “He doesn’t”
Using double negatives:

Incorrect use of two negative words in a sentence, e.g., “I don’t need no help” instead of “I don’t need
any help”
Misusing”effect” and “affect”

“Effect” is a noun referring to a change that occurred.
“Affect” is a verb meaning to produce a change.
Confusing “lose” and “loose”

“Lose” is a verb meaning to be unable to find or retain.
“Loose” is an adjective meaning not tight.
Mispronouncing or misspelling commonly used words:

Examples include “irregardless” instead of “regardless” or “definately” instead of “definitely” It’s essential to keep in mind that language is dynamic, and mistakes can happen to native and non- native speakers alike. Continuous practice, reading, and exposure to the language can help improve
proficiency and reduce these common errors. Additionally, proofreading and seeking feedback can be valuable tools in refining language skills.