(watch/ring)

2. Jack his presentation when the fire alarm (finish/start).

3. Just as I my front door, a cat inside. (open/run).

4. My mom me while I dinner. (telephoneleat).

5. While i to work, i an accident (walk/witness).
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1. While I was watching TV, the doorbell rang. 2. Jack was finishing his presentation when the fire alarm started. 3. Just as I opened my front door, the cat ran inside. 4. My mom telephoned me while i was eating dinner. 5. While i was walking to work, i withessed an accident.

we have become more dependent on chemicals.  and, strangely, we hardly notice anymore. every single day we start and finish by using a product that has at least 10 different chemicals in it: a toothpaste. later, we take a shower using several products (shampoo, conditioner, body wash, lotion). the names of the chemicals in all these products will take a few pages to list. later on, we eat chemically enhanced food, packaged in plastic.  we wear and sleep on synthetics, we drink and eat foods that are drastically modified with chemicals.  all these innovations have been introduced less than 50 years ago, just two generations have been around so many chemicals lately.  and, scarily enough, we hardly notice anymore.

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