1. She's a cabin steward for Air China and she ______ (fly) all over the world.
2. My grandparents always eat Chinese food, they ______ never ______ (have) a west food.
3. How many English words ______ you ______ (learn)?
4. I______ never______ (speak) to a foreigner.
5. —______Tom______ (return) the library book? —Yes, he has.
    —When ______he______ (return) it? —Half an hour ago.