Writing exercises

 Physical attraction is important for marital happiness.
Physical attraction is certainly important for marital happiness.

 Economic sanctions are ineffective.
Economic sanctions might be ineffective.

 Alcohol causes people to become violent.
Alcohol may causes people to become violent.

 Passive smoking causes cancer.
Passive smoking can causes cancer.

 Recycling is the best solution to the waste disposal problem.
Recycling seems to be the best solution to the waste disposal problem.

 Physical exercise lessens the severity of depression.
Physical exercise highly likely lessens the severity of depression.

 Great novels do not make great films.
There is a good possibility that great novels do not make great films.

 Private schools provide better education than do public schools.
Private schools usually provide better education than do public schools.