A double negative is a no-no. Author unknown

Only in grammar can you be more than perfect. William Safire

And all dared to brave unknown terrors, to do mighty deeds, to boldly split infinitives that no man had split before—and thus was the Empire forged. Douglas Adams in The Hitchhiker’s Guide to the Galaxy

The past is always tense, the future perfect. Zadie Smith

I really do not know that anything has ever been more exciting than diagramming sentences. Gertrude Stein

A preposition is a terrible thing to end a sentence with. Winston S. Churchill

If rhetoric study was the military, grammar teachers would be the drill sergeants. T.K. Naliaka

Grammar is like your overarching compulsion. It’s math with words. Thomm Quackenbush

The past, the present, and the future walked into a bar. It was tense. Lex Martin

 

As far as I’m concerned, ‘whom’ is a word that was invented to make everyone sound like a butler. Calvin Trillin