________ your mother ________ carrots?

These increased harvests _____ that 22% of the world’s people are fed from just 7% of the farmland in China.

 Our school has about 100 computers, but only sixty percent ____ used regularly.

The teacher，with 6 girls and 8 boys of her class，_____ visiting a museum when the earthquake struck.

There are many boys     football in your school.