Few, which emphasizes the fact that the number is small should be distinguished from a few which emphasizes the fact that there is a number though it be small. "Few shall part where many meet." "A few persons were saved in the ark."
Fewer applies to number; less to quantity.
Firstly should not be used for first although secondly and thirdly may be used to complete the series.
Fix should not be used in the sense of repair, arrange, or settle.
Former and latter should never be used where more than two things are involved.
Frequently should be distinguished from commonly, generally, perpetually, usually. Commonly is the antithesis of rarely, frequently of seldom, generally of occasionally, usually of casually.
Funny should not be used to mean strange or remarkable.
Gentleman Friend and Lady Friend are expressions which should be avoided, say "man or woman friend" or "man or woman of my acquaintance" or even "gentleman or lady of my acquaintance."
Good should not be used in the sense of well. "I feel good."
Got is said to be the most misused word in the language. The verb means to secure by effort and should be used only with this meaning, e. g., "I have got the contract." Have got to indicate mere possession is objectionable. Mere possession is indicated by have alone. Another common mistake is the use of got to express obligation or constraint. "I have got to do it."