We were swimming in the lake __________ suddenly the storm started.
I was so familiar with him that I recognized his voice I pick up the phone.
---How often do you call your parents? ---,but usually once a week.
Though computers can do a lot of work man can’t do, they can’t completely _______ human beings.
Can you think of some cases________drivers obviously knew the traffic rules but didn't obey them?
Film has a much shorter history, especially when such art forms as music and painting.