The dog wagged its tail happily.

Don't wag it, just do your homework.

The dog was wig-wagging its tail happily.

She was finger-wagging at him for being late.

The tail wagging the dog is a common phrase used to describe a situation where a small or unimportant part is controlling the whole.

We had a good chin wag over a cup of coffee.

We had a good chin-wag over a cup of coffee.

The wag-on-the-wall clock was a unique addition to the room.

The antique clock on the wall is wag-at-the-wall.

I love having chin-wags with my friends.