One of the responsibilities of the Coast Guard is to make sure that all ships______followtraffic rules in busy harbors.

In order to buy a new car, you should at least ______ one hundred dollars a week.

If you’re sitting around a lonely campfire at night, the howl of a wolf can sound pretty______.

The suspect cooperated fully with the police when ______ about his role in the incident.

In 1900, the energy derived from burning petroleum was only four percent ______ of coal.