_____ many times, but he still doesn’t know how to operate the machine properly

What do you think makes a good doctor—As doctors, they can’t be ________ careful. They must have perfect medical skills.

Mary wrote an article on ________ the team had failed to win the game

It’s too hot. Would you mind ________the door—-________. Please do it now.

In the future, care for the environment will become very important as earth’s natural resources _____.