Identify an error in each sentence.

The legal age which (A) a person is considered (B) to be an (C) adult is customarily (D) 18.

Choose the best answer to complete each sentence.

China has already been experimenting with ways to make its cities more ______ for the last two decades.

Choose the best answer to complete each sentence.

New York has invested substantially in improving the ______ of its waterways in recent years.

Choose the best answer to complete each sentence.

We will need new technologies to generate energy and use it in clean and safe ways, only from fully ______ sources.

Choose the best answer to complete each sentence.

Vancouver is often considered to be one of the most ______ cities in the world.

Choose the best answer to complete each sentence.

As we move toward 2050, we are facing the consequences of _____ urbanization and population growth.

Choose the best answer to complete each sentence.

Telecommunications and cloud computing will ______ transportation for moving ideas and intellectual property.

Choose the best answer to complete each sentence.

Copenhagen has been voted the most ______ city in the world several times.