There are two fabulous verbs in English that are constantly dissed by being hopelessly confused with each other. I’ve heard highly sophisticated people confound these two wonderful work horses, and I’ve seen writers for the New York Times and the London Review of Books do it. Why, — birds do it, bees do it, educated fleas do it and … in Boston even beans do it! But never have I (yet) come across this unpleasantness in the pages of The New Yorker, in my view the best overall venue for very good, pleasurable modern American English.
Let’s look at the PRINCIPAL PARTS (Oh, don’t know – or, rather, forgot? — what they are? Back with you to, e.g., the fourth grade or this school!) of the two verbs [be thankful that we have generally only three of them for English verbs – Latin has four and ancient Greek as many as six or more, depending …]:
intransitive lie lay lain
transitive lay laid laid
intransitive lie lay lain lying
transitive lay laid laid laying
The present tense of the transitive verb looks (and sounds) exactly like the simple past tense of the intransitive one. Hence, when one comes across inadvertently amusing lexical chimaeras like this, “He is laying on the bed,” one’s immediate impulse is to ask who his S.O. is – but, needless to say, one bites one’s impudent tongue and swallows the incipient smile.
Perhaps the following will be a helpful way to think of this matter:
“I lay the book on the table and now the book lies on the table.”
“I laid the book on the table and then the book lay on the table.”
“I have laid the book on the table and now the book has lain on the table.”
Apply them mutatis mutandis.
(Oh, don’t know – or, rather, forgot? – what that phrase means? You know what’s … next!)
It really isn’t all that difficult!