The children are making __________. How __________ they are playing!

Would you ________ close the window? It’s very cold.

They want to develop a kind of dog-friendly food _____ will help dog owners cool down their pets. [ ]

Are you interested in learning math?—Yes, but I’m afraid to _______ too much time on math.

The ancient penguin was modern ones and it was good at swimming but couldn’t fly.