If you have something important to do, you ___ waste any time.

If we work hard with a strong will, we _____ overcome any difficulty, however great it is．

We would rather the UN immediately ________ effective measures to settle the present conflicts between the two countries.

I’m really sorry, Lucy. I ______ to help you, but I was too busy at that time.

I was on the highway when this car went past followed by a police car. They ______ at least 150 kilometers an hour.