1. Was, had done.
2. Had ended, fell asleep
3. Felt, had eatten
4. Arrived, found, had just left
5. Had made, sat, drenk
6. Walked, had missed
7. Had got, had spent.
8. Decided, had been
9. Signed, had come.
10. Phoned, said, had seen
What tv 6 make snowman 5 read book 3 play in the snow 1 go camping 7 go skiling 2
1.
1 No, they haven't
2 Yes, I have
3 Yes, they have
4 Yes, I have
5 No, he hasn't
2.
1 The bought their new car last month.
2 They have just done their homework.
3 They met in a small cafe yesterday.
4 My sister hasn't arrived from Moscow yet.
5 I have already been there.
3.
1 Yesterday my father washed his car.
2 I have just done my homework.
3 My parents went to Turkey last year.
4 My friend 's sister hasn't bought tickets at the zoo yet.
5 Did you go to the cinema yesterday?
6 Has her brother ever gone abroad?
1. Steel - its alloy and the most important metal in industry is iron.
2. Steel is strong and stiff.
3. Steel corrodes easily through rusting.
4. Stainless, steels of low carbon content, medium-carbon steels, high-carbon steels and silver steel. The used in the manufacture; used as structural steels; used in cutting tools, surgical instruments, razor blades and springs.
5. Manganese gives extra strength and toughness. Steel containing 4 per cent silicon is used for transformer cores or electromagnets because it has large grains acting like small magnets. The addition of chromium gives extra strength and corrosion resistance, so we can get rust-proof steels.
6. Of mild steel can made sheet iron, wire, and pipes. Of medium-carbon steel can made structural steels.
Of high-carbon steels made cutting tools, surgical instruments, razor blades and springs.
7. Both mild and medium-carbon steels are suitable for forging and welding.
8. The addition of chromium gives extra strength and corrosion resistance, so we can get rust-proof steels.
9. Heating in the presence of carbon or nitrogen-rich materials is used to form a hard surface on steel.
10. High-speed steels alloyed with contain chromium and tungsten plus smaller amounts of vanadium, molybdenum and other metals.