Grammar moment: Oh, those confusing verbs!
Intransitive: lie -- to recline
Present tense: I lie on the beach all the time. WCMIK lies on the beach all the time.
Past tense: I lay on the beach yesterday.
Present participle: I like lying on the beach.
Past participle: I have lain on the beach every day for a month.
Transitive: lay -- to put (something) down
Present tense: I lay flowers on the memorial every month. WCMIK lays them too.
Past tense: I laid flowers there yesterday.
Present participle: Laying flowers is a valuable tradition.
Past participle: I have laid flowers for many years.
Intransitive: sit -- to be seated
Present tense: I always sit in the front row at the cinema. WCMIK always sits in the front row.
Past tense: I sat in the front row yesterday.
Present participle: Sitting in the front row is good.
Past participle: I have sat in the front row for ages.
Transitive: set -- to put (something) down
Present tense: I set the table every day. WCMIK sets the table every day.
Past tense: I set the table yesterday.
Present participle: My favorite chore is setting the table.
Past participle: WCMIK has set the table for years.
Intransitive: rise -- to get up
Present tense: I rise every day at noon. WCMIK rises every day at noon.
Past tense: One day, many years ago, I rose at eleven.
Present participle: Rising earlier doesn't work for me.
Past participle: I have risen at noon for most of my life.
Transitive: raise -- to lift or bring (something) up
Present tense: I raise well-behaved cats. WCMIK raises well-behaved cats.
Past tense: My old English teacher raised well-behaved cats when I was a kid.
Present participle: Raising well-behaved cats is essential.
Past participle: Smart people have raised well-behaved cats since the days of ancient Egypt.
All of this may be difficult to memorize; the best way to learn is through practice. But the key question to ask, whichever of these verb pairs is giving you trouble, is "Is there a direct object? Is this action being done TO something?" If the answer is yes, you use the transitive form. If not, use the intransitive.
Finally, a word to all of the dog owners and trainers out there: Please stop teaching your pets improper grammar! Don't command them to "lay down" when what you really want them to do is "lie down."