________ you ought to do now is to see a doctor at once.
The half smile on the little hero’s face seemed to suggest that he was happy __ his life for his country.
He forgot to turn off the light.So he went to bed with the light ___on.\
Asia is the largest continent, ___ one third of the earth’s land area.
After many months of hard work, they manager __ off all the debts.
Mike is taller than __ students in the class.