Electricity, like other forms of ______, has greatly increased in price in recent years.
So far nobody has claimed the money ___ in the library.
The workers ___ the glass and marked on each box“This Side Up”.
More and more high-rise buildings have been built in big cities ___ space.
Some insects ___ the colour of their surroundings to protect themselves.
You had better ___ some time every day for sports so that you can keep your energetic.