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1. G        was once much used for lighting and is now used for cooking and heating.

2. Modern life depends on good t         .

3. Eating too much c         is bad for your teeth.

4. We should learn much more history k         .

5. They are waiting for their friends on the p        at the station.

6. He always has some d         ideas in his mind.

7.I have collected a few a       coins these years.

8. They'd like to d         their. rooms with a Christmas tree and some fresh flowers.