21.   His shrimp sickened and died, and his two half-acre ponds now lie stagnant and toxic, useless for further cultivation.

22.   If strong resistance to a drug develops in a population of germs, the drug may become useless for some conditions.

23.   It does not have a cardiovascular system, however, making it useless for studying heart disease.

24.   It is useless for everyone else.

25.   Like plutonium it can be used to make bombs, but larger quantities are needed and it is more easily rendered useless for weapons through mixing with natural uranium.

26.   Like the worst invasives, it pushes out all other vegetation, rendering natural areas useless for most wildlife and recreation.

27.   Like early maps of the world, they tend to be incomplete, distorted and virtually useless for navigation.

28.   Much of the glass downtown either was rendered useless even for recycling or it was not the right kind of glass, Russ said.

29.   Palm-size computers are handy to carry, but the tiny keyboards make them almost useless for typing in pages of notes.

30.   Pentamidine is useless for these people.