The professor has received the letter ____ to give a lecture in ftinceton Institute.
. Many people complain of the rapid _____ of modern life.
. The government is _____ and will take the necessary steps to maintain security and stability.
Carl wanted to play a joke on Bob but gave himself _____ by laughing.
The rapidly growing birth rate brings about a lot of environment problems, which the government is supposed to take _____.
The two dogs started to fight, so we tried to _____ them.