During the next ten years we both worked day and night to _____ the money we had borrowed.
A middle-aged woman came ____to the bus stop only ___ the bus had gone.
Every boy and every girl as well as some teachers who ___ to visit the museum _____required to be at the bus station at 6:30.
I’ll never forget such an attractive city ___ I spent many happy hours there with my classmates last summer holidays.
______ , I think , and the problem could be settled.
At home, he keeps some pets, to which he _____ all his spare time.