One idea per paragraph is the rule everyone knows. What matters more is that the first sentence tells the reader what the paragraph will do.

“Furthermore” and “moreover” are usually signs a writer has lost the thread. Real transitions come from the order of your ideas, not from a word list.

A cliché is not wrong. It is invisible — the eye slides over it, and whatever you meant slides past with it.

Items in a list must share a grammatical shape. Break it and the sentence stumbles in a way readers feel without being able to name.

“The implementation of the solution” was once “we solved it”. Nominalisation is the single biggest cause of writing that is grammatically perfect and unreadable.

Free gift. Advance planning. Past history. Each one contains a word doing nothing, and most people have said all three this week.

Prose where every sentence runs the same length reads as flat, however correct it is. Variation is the fix, and it is almost mechanical.

English rearranges the sentence to ask a question, and then inserts a helper verb that was not there before. Few languages make you do both.

Who, which, that, whose and where let you attach a whole clause to a noun. The comma decides whether the information is essential.

Three tiny words governing when and where, with a pattern underneath that most textbooks never state.