Paper books still play an important role in the US textbook market, with digital textbooks __________ less than 5 percent of the total.
She must face up to _______ she is no longer young.
They knew nothing about ______ he was a thief.
We were all worried over _______ you were sick.
“You went late _______ the stadium yesterday evening, didn’t you?” “Yes, my wife was a little late _______ the supper.”
“I think you should phone Jenny and say sorry to her.” “______. It was her fault.”