While we were listening to the speech attentively, a voice _____ to announce the result of the election.

To reduce the pressure of traffic in our city, the government _____ banning cars in the city centre.

The math problem is so hard, I really don’t know _____.

If they don’t come to their senses,they will _________ up in the same grave as Hitler.

Tony, be quiet, please! Your dad ______ onthe phone.