1. Urgent action is needed to solve the problem of homelessness.

2. Enormous efforts have been made by scientists to find a cure for this disease.

3. The very thought of his face at that moment makes me laugh.

4. There was an agreement among the teachers to introduce the new methods.

5. The boy dances to his father's tune in an obedient way.

6. I have some colleagues whose attitudes to work I simply fail to understand.

7. I did not realize the extent to which he was influenced by his brother.

8. Mass tourism is implicated in causing environmental problems.