a. complete the sentences, put the verb into the correct form, positive or negative. (simple past tense). 1. it was warm, so i took off my coat. (take). 2. the film wasn't very good. i didn't enjoy it very much. (enjoy). 3. i knew sarah was very busy, so i didn't disturb her. (disturb). 4. i was very tired, so i wentto bed early. (go). 5. the bed was very uncomfortable. i didn't sleep very well. (sleep). 6. sue wasn't hungry, so she didn't eat anything. (eat). 7. we went to kate's house but she wasn't at home. (be). 8. it was a funny situation but 12. it was hard work carrying the bags. they were very heavy. (be)
Task 1
1. Both the metals and the polymers can be alloyed.
2. It is possible to develop polymeric substances with the scheduled properties.
3. The so-called "aging" of the polymers is due to chemical and physical changes caused by the effect of light, heat and humidity.
Task 2
1. Polymers are characterized by their viscosity colour and softening points.
2. The properties of the polymers depend on their super-molecular structure.
3. The main concern of researchers and engineers is to improve the quality of mass produced goods.
Task 3
1. Polymers are widely used in industry.
2. Light, heat and humidity affect the polymers.
3. The main concern of the researchers and engineers is to improve the quality of polymers.