81Male and female students are quite different from each other ______ the age at which they begin to develop an intellectual self-discipline

It’s said that ________ gains from house sales should pay the individual income tax.

The farmer ___ cows and corn

Military helicopters dropped food and medicine to the earthquake survivors that remained ________ in remote mountain villages.

I called you at 8:00 yesterday evening, but no one answered. —Sorry. I________ clothes for my parents at that time.