The joints must keep opening because of expansion and contraction.

I kept opening other doors for him and he still wouldn't leave.

There isn't any rain in hell So why keep opening an umbrella?

Bernard, who neither smoked nor drank, had to keep opening the windows.

The little man kept gulping and opening his mouth like a fish.

Joe knew differently, however, for you couldn't keep opening an elevator door if the car wasn't there.

Yet we will keep opening the doors; we cannot be stopped.

I keep opening my mouth, but nothing comes out.

And if there's only one fridge that everyone keeps opening to get ingredients, it will take even longer.

It was freezing in that car today, he kept opening the window.