Your grammar, it sucks like the black hole on a cloudy day. If you do not become the grammar master, you may loose your readers who will not be coming back.
(Oh, how it hurts to type that.)
Grammar is not just the green squiggly line under most of your sentences in MS Word. Nor is it something your septuagenarian English teacher invented because your stories were just so edgy, so radical, he had to fail you.
Words are not distributed randomly in sentences. If you want to be understood by your readers, you place words in a certain order, based on common rules. In case you’ve forgotten, we call these rules grammar.
(This casual definition is worded specifically to fibrillate the hearts of the Grammar Nazis, who trawl the Internet looking for dangling participles and plural noun confusion, and who secretly hope that I am one of them. Fsck you, Nazis! It must be so hard to clean that glass house in which you live.)
Unless you’re over 40, you may not know what I’m talking about, because public schools stopped teaching grammar sometime around 1970. Now, even the teachers don’t understand it.
This is both the problem, and part of the solution. If you don’t know what an infinitive is, let alone how to stop splitting them, you can be sure that 99% of modern readers couldn’t care less. The world has moved on from the expectation of syntactic exactitude - now you’re considered “bright” if you can read a newspaper after 12 years of schooling. What matters is whether readers can interpret meaning from your sentences.
If your grammar is terrible, which is extremely likely, readers will have a difficult time trying to work out what the fsck you’re on about. On the other hand, if your writing is grammatically perfect, you may pass the “old fogey” test but most readers will find your writing stiff and boring, and many will find it just as difficult to read.
A common understanding of grammar is the primary method by which you communicate your ideas to the reader. (I say “primary” because your writing is still full of dull, lazy cliches which communicate old ideas to the reader who already understands them, but that’s another Reason entirely.) If you don’t have this common understanding of how readers turn each sentence into something approximating what you meant, your work is going into the bin before the end of page 1.
Sure, you can learn the rules of grammar, just as you can learn to say “How much for the private dance with the happy ending” in another language. There are some fine books on the (former) topic. But unless you already have a good understanding, you’ll never pass for a local, and you’ll always wind up overpaying.