The children have been （ ） since their father left．

The bad weather （ ） the building program by several weeks．

Solar energy is a new kind of energy _____ that we can use to replace the traditional energy.

Jean did not have time to go to the concert last night because she was busy （ ） for her history examination.

We are at your service. Don’t （ ） to turn to us if you have any problems.

The meeting is to begin at 4:00 p.m., but as assistants, we’re （ ） to be there a bit earlier.

Our English professor is a man of French （ ）.

Just as the soil is part of the earth, （ ） the atmosphere.

When we arrived at the airport, we were told our flight （ ）.

To be frank, （ ） is a great relief to have the task fulfilled in so short a time.

Please let us have more time to play outside， _____?

All （ ） is to give him a warning.