It _____ four years since we ______to learn English.
—Mother’s Day is coming. I’m going back home to see my mother. -- ______.
The scientists told us _______ about three days from Earth to the moon by spaceship.
My sister likes eating _______, but I don’t like eating them.
-- _______ is the man in the white shirt? -- He is an engineer.
In our library, the number of books ________ more than 40,000.