Rewrite sentences with weaker verb

1. Attractive people can have more favorable personal attributes than unattractive people.

2. Economic sanctions are possibly ineffective.

3. Alcohol usually causes people to become violent.

4. According to the report, passive smoking can highly causes cancer.

5.Recycling could be the best solution to the waste disposal problem.

6. Some of the evidence shows that physical exercise prevents depression.

7. Deep tunnelsare are presumably safer and less vulnerable to earthquake shaking than are shallow tunnels.

8. Private schools can possibly provide a better education than public schools.