Monday, October 29, 2018

Toefl Listening Practice - Main Idea Part 3




8. What is the main subject of this lecture?
a) The failures of the United Nations
b) The historical role of the League of Nations
c) The origins of World War II
d) The forgotten successes of the League of Nations

9. What is the main idea of this lecture?
a) Despite certain advantages, there are any problems involved in the use of hot dry rock technology.
b) Hot dry rock technology is too expensive to ever be used as a practical energy source.
c) The main purpose of hot dry rock technology is to provide pure, clean water.
d) hot dry rock is a potentially important alternative source of energy.