Links in this essay will take you to information about the usage experts and their work. Numbers in parentheses are page references in the sources.
lie versus lay
If you have trouble keeping the meanings and the forms of lie and lay straight, you are not alone. According to The New York Public Library Writer's Guide to Style and Usage, "Even the most experienced writers and editors sometimes run to their grammar books when confronted with lay—to put or to place—and lie—to recline, rest, or stay" (147). Kenneth Wilson echoes the point: "Many Americans who are otherwise users of Standard English err with lie and lay and as a result fearfully seek another way of saying what they have in mind" (267).
In informal, spoken English, many people break the rules all the time. In particular, they use lay instead of lie and laying instead of lying: I'm going to lay out in the sun. He is laying down. The American Heritage Book of English Usage asks us to be tolerant of such misuses in informal speech. The editors write, "What if Bob Dylan, in a fit of zeal for correctness, had written 'Lie, Lady, Lie / Lie across my big brass bed'? Somehow it's hard to imagine the lady sticking around" (114).
Although they acknowledge that many people break the rule, most experts don't excuse us from getting our lies and lays straight—at least in formal writing. H. W. Fowler describes the rules on lie and lay as "merciless, admitting no exceptions in standard English" (445). The American Heritage Book of English Usage cautions writers to "keep the two verbs distinct in formal writing, since people will be looking for evidence of your education in your work" (114).
Conclusion: In speech, you can often get away with breaking the rules on lie andlay. When writing, however, keep your grammar book close by.
Source: Hacker Handbooks (Boston: Bedford, 2013)