The boy is old enough to __________ the difference __________ right and wrong.
Though he is still a child, he has already read _____ 1,000 books.
With online course Crazy English has over 20 million students all over China _____the class through the Internet.
–There were already five people in the car but they managed to take me as well. --It _____ a comfortable journey.
–Why, I couldn’t get you on the phone this morning. --We _____ tennis in the yard when you called.
Tom as well as his classmates _____ Japanese in Japan.