Put the verbs in brackets into proper tense form.

1. Many things just (to remain) the same.

2. Steel (to be) still the basic material of armaments.

3. The Roman world (to know), at least, copper, lead, gold, silver, tin, dion, mercury and zinc.

4. By the next month he (to analyze) all the properties of titanium.

5. Metals and nonmetals (to enter) actively into chemical reactions now.

6. These metals (to be) considered to be metals 100 years ago.

7. He said that he (to distinguish) the properties of tungsten.

8. Romans (can) name only some metals.

9. Knowledge of the metals (to increase) since Caesar’s day.

10. Those elements that (to possess) high electrical conductivity and a lustrous appearance in the solid state (to be) considered to be metals.

6. Give short answers to the following questions:

Model: Has knowledge of the metals increased? - Yes, it has.

Did the Roman world know all the existing metals? - No, it didn’t.

1. Is steel still the basic material of armaments? - Yes, …

2. Did the Roman world know the properties of tungsten? - No, …

3. Is copper the Erin coinage metal? - Yes, …

4. Do we use uranium to resist the corrosive action? - No, …

5. Does nonmetal enter actively into chemical reactions? - Yes, …

6. Answer the following questions:

1. How has the knowledge of metals changed since Caesar’s day?

2. What metals did the Roman world know?

3. What metals does the present man know?

4. Is oxygen a metal?

5. Is iron a metal?

6. Where does the difference between metals and non-metals lie in?

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