24. —Who______ it be that is knocking at the door? —It ______ be father, but I’m not sure.
They started early that morning in order that they_____ there before noon.
Mary cares about clothes too much, and she _____ too much money _____ clothes.
"_____ of them are not here." means "_____ of them are not here."
We must do something to _____ factories _____waste water into the river before it is cleaned.
What way are you thinking of _____ rid of the flies?