—Who______ it be that is knocking at the door? —It ______ be Father, but I’m not sure.
It was not until midnight __________ they reached the camp site.
We finished the run in less than half the time __________.
Vitamin C helps our bodies make a special chemical, which __________ affects our brains, making us feel happy.
He put forward his suggestion at the meeting that every means __________ to save the crops before the storm came.
No matter how low you consider yourself, there is always someone __________ you wishing they were that high.