grammar - "He lay on the bed gazing up at the ceiling." - Is this sentence from a dictionary correct?

In the definition article of "gaze" (MacMillan Dictionary) I found the following example sentence:

He lay on the bed gazing up at the ceiling.

I cannot figure out what form "he lay" should be. My alternatives are "he lays" or "he laid" but not "he lay".

Is that sentence correct? If yes: what form is "he lay"?

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Ohhh! After reading the answers (thx!), I found the source of my confusion: in this online dictionary you can click on each word and you would be forwarded to its definition. Clicking on "lay" in this sentence forwards to "lay (verb)" what is obviously a tricky linking error of the dictionary.

Answer

Lay in this case is the past of "lie", which is an intransitive verb. The difficulty occurs because "lay" can be a form of two different verbs which have similar meanings:

1. lay, laid, laid (transitive): to put someone or something down in a careful way, especially so that they are lying flat https://www.macmillandictionary.com/dictionary/british/lay_1


2. lie, lay, lain (intransitive): to be in a position in which your body is flat on a surface such as the floor or a bed https://www.macmillandictionary.com/dictionary/british/lie_1

Even native speakers get tripped up on the proper forms. "Lain" in many cases sounds old-fashioned to some people.