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1. What are metals and what do we call metallurgy? Materials most widely used in industry, the study of the production and properties of metals 2. Why are most metals dense? The atoms are arranged regularly 3. Why are metals malleable? The atoms can slide over each other. 4. What is malleability? atoms' sliding over each other. 5. What are grains? Irregular crystals 6. What is alloying? Adding small amounts of other metals 7. What is crystalline structure? Regular arrangement of atoms 8. What do the properties of metals depend on? The properties of the metals depend on the size, shape, orientation, and composition of these grains. 9. What changes the size of grains in metals? Quenching, tempering, or annealing 10. What are the main processes of metal forming? Drawing, rolling, hammering and extrusion, but some require hot-working. 11. How are metals worked? Using machine-tools such as lathe, milling machine, shaper and grinder 12. What is creeping? The slow increase in length under stress.

1.Alice and Ron.are sitting in a cafe now.

2.It isn't snowing outdoors now.

3.We are waiting for out teacher in the classroom.

4.I am watching the children playing in the yard.

5.The girls are arguing about what present to buy for Lewis.

6.Andrew isn't having a rest at the moment.

7.Look!All the people are coming into the hall.

8.Unfortunately our experiment isn't getting according to the plan.

9.Pam is standing too close to the road.

10.The students aren't having a lecture now.

11.Her health is improving day after day.

12.The rainforests are disappeaing from our planet nowadays.

13.The baby-sitter isn't looking after the child because the child is sleeping now.

14.Look!The guide is pointing at some ancient building.

15.I am not discussing this question now