Fill in the words from the list below. Use each word only once.

electricity, common, elements, melting, development, large, extent

1. the world's most ….. metal

2. comparatively large …..

3. classification of the ….. groups

4. reasonably ….. quantities

5. comparatively high ….. point

6. good conductors of heat and …..

7. cultural stages in human …..

7. Read the text and fill in the gaps with the words from the list below. Use each word only once:

metal, important, century, obtain, useful, brass, alloys, copper, environment

It is only since the time a man had learnt how to 1) _______ and use metals and their 2) _______, he has been able to adapt his 3) _______ to his needs and desires. The present age is, in fact, the Age of Metals and it is 4) _______ that we should have some acquaintance with these 5) _______ substances. In the ancient times, gold, silver, 6) _______, tin, iron, lead and mercury were known as "The SevenMetals".

One other 7) _______, zinc, has also been known in its role as one of the constituents of the alloy 8) _______. Almost no metals other than these seven or eight were known until the eighteenth 9) _______ and many that we use today, not until the nineteenth.

8. Read the clues and complete the crossword:

								^1
					^2
		^3
						^4
^5
				^6
			^7
^8
		^9
		^10

Across:
	A metal that consists of two or more different metals mixed together.
	Something that acts as a path for electricity, heat, etc.
	A valuable soft yellow metal that is a substance and is used for making jewellery.
	The act of separating or the fact of being separated.
	The process during which a solid becomes liquid.
	A soft whitish precious metal that is a simple substance, carries electricity very well, can be brightly polished and is used in jewelry, coins, knives and forks.

Down:
	A soft reddish metal that is a simple substance, is easily shaped and allows heat and electricity to pass through it easily.
	A very common and useful metal that is a simple element, is magnetic, is used in making of steel and is found in very small quantities in blood.
	Any usually solid shiny mineral substance which can be shaped by pressure and used for passing an electric current.
	The process of corroding.
	Anything from which something is or can be made; natural or man-made substance.

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