It is obvious that water is to be _____to the development of life.

Our teachers are really ______. They often work in their office far into the night.

The study surveyed 500 families and found the main   problem people suffered was tiredness, followed by loneliness and anxiety.

Mr. Green kept ______ and complete records of all his business expenses.

What___ it is to have a cold drink after an _____ game!