Lay 'lie, lay, laid and lain' confusion to rest

If you already know the difference between  lie, lay, laid and lain you can smugly go and do whatever you want. For the rest of us, let's lay the confusion to rest, once and for all!

To understand the difference between these words you just need to know that we use verbs to describe something we are doing right now (present tense), something we have done already (past tense) and something we will do after this point in time (future tense). There are other variants as well, but those are the basics.

The key to using these words is just work out if you are talking about something that is happening right now, or something that happened in the past.

Lie

Lie mainly refers to being in a horizontal position on a supporting surface.

In the present tense (happening right now) we can say

I lie on the bed.
I am lying on the bed.

In the past tense (already happened) we can say

I lay on the bed.
I had lain on the bed (...for what felt like a minute and then the alarm clock went off.)

Lay

Lay mainly refers to putting down something gently or carefully, or putting something down and setting it in position for use.

In the present tense (happening right now) we can say

I lay the floor tiles in position.
I am laying the floor tiles in position.

In the past tense (already happened) we can say

I laid the floor tiles in position.
I had laid the floor tiles in position. (...when the next door neighbours' dog came running over them and messed them up. Just saying.)

Once you have worked out what you are doing (lying horizontally or placing something) you can easily choose the correct word.