Swash and backwash

Do you know which is the swash and which is the backwash?

The swash is the surf moving up the beach. The backwash is surf running back down the beach.

Say out loud SWASH when you see surf running up the beach. You should make SWAAAAAAASH last as long as you can see it.

Then say out loud BACKWAAAAAAAASH for as long as it takes the surf to go back out again.

Try to make the words SWASH and BACKWASH sound like the noise you hear.