课文填空 (共5小题，每小题1分，满分5分)
根据课文内容，准确补充完整下列句子，完全正确方可得分。
1. _______________________ the earth is becoming warmer (see Graph 1) and that it is human activity that has caused this global warming rather than a random but natural phenomenon.
2. It will those who love Impressionist and Post-Impressionist paintings.
3. When I was young, I didn’t know much about the harmful of smoking.
4. They also agree that it is the burning of more and more fossil fuels that has __________ this increase in carbon dioxide.
5.I was as a volcanologist working for the Hawaiian Volcano Observatory (HVO) twenty years ago.
