Shelf, photo, day, tooth, flower, hero, cliff, factory, box
3. Перепишите предложения. Определите видовременные формы глаголов. Укажите их инфинитив и переведите предложения на русский язык.
a) We shall have a History class tomorrow.
b) Andrew devotes a great deal of time to reading.
c) A dog stole a large piece of meat and ran away.
4. Перепишите следующие предложения, поставив прилагательные в скобках в нужную степень, и переведите предложения на русский язык.
a) This is the (comfortable) room in the house.
b)My daughter is (young) than yours.
c) Winter is the (cold) season.
5. Прочитайте и переведите текст.
Sheet metal forming
Sheet metal forming (штамповка листового металла} is widely used when parts of certain shape аnd size are needed. It includes forming, bending and shearing. One characteristic of sheet metal forming is that the thickness of the sheet changes little in processing. The metal is stretched just beyond its yield point (2 to 4 percent strain) in order to retain the new shape. Bending can be done by pressing between two dies. Shearing is а cutting operation similar to that used for cloth.
Each of these processes may be used alone, but often аll three are used on one part. For example, to make the roof of an automobile from а flat sheet, the edges are gripped and the piece pulled in tension over а lower die. Next an upper die is pressed over the top, finishing forming operation (штамповку), and finally the edges are sheared off give the final dimensions.
Forging
Forging is the shaping of а piece of metal by pushing open or closed dies. It is usually done hot in order to reduce the required force and increase the metal's plasticity.
Open-die forging is ussua11у done by hammering a part between two fat faces. It is used to make parts that are too big to be formed in а closed die or in cases where only а few parts are to be made. The earliest forging machines lied а large hammer that was then dropped on the workpiece but nosy air or sham hammers are used. since they allow greater control over the force and the rate of forming. The part is shaped by moving or turning it between blows.
Closed-die forcing is the shaping of hot metal within the walls of two dies that соте together to enclose the workpiece on all sides. The process starts with а rod or bar cut to the length needed to all the die. Since large, complex shapes and large strains are involved, general dies may be used to go from the initial bar to the final shape. With closed dies, parts can be made to close toletances sо that little finish machining is required.
Вариант 7.
1. Перепишите следующие предложения, вставьте артикли там, где необходимо и переведите предложения на русский язык.
а) ... Saransk is the capital of... Mordovia.
b) There is... picture on the wall.
c) This is... highest building in the city.
d) What . . . interesting book.
2. Образуйте множественное число существительных.
Life, factory, plane, brush, day, mouse, tomato, roof, school
3. Перепишите предложения. Определите видовременные формы глаголов. Укажите их инфинитив и переведите предложения на русский язык.
a) Не will get a good job after graduating from the University.
b)Mrs. Grey seldom cooks meals at home.
c) I brought him two magazines last week.
4. Перепишите следующие предложения, поставив прилагательные в скобках в нужную степень, и переведите предложения на русский язык.
a) Iron is the (useful) of all metals.
b)The Neva is (wide) and (deep) than the Moskva River.
c) Elbrus is the (high) peak in the Caucasian mountains.
5. Прочитайте и переведите текст.
"STEEL"
The most important metal in industry is iron and its alloy — steel. Steel is an alloy of rоn and carbon. It is strong and stiff, but corrodes easily through rusting, although stainless and other special steels resist corrosion. The amount of carbon in а steel influences its properties considerably. Steels of low carbon content (mild steels) are quite ductile and are used in the manufacture of sheet iron, wire, and pipes. Medium-carbon steels containing from 0.2 to 0.4 per cent carbon are tougher and stronger and are used as structural steels. Both mild and medium-carbon steels are suitable for forging and welding. High-carbon steels contain from 0.4 to 1.5 per cent carbon, are hard and brittle and are used in cutting tools, surgical instruments, razor blades and springs.'| Tool steel, also called silver steel, contains about 1 per cent carbon and is strengthened and toughened by quenching and tempering.
The inclusion of other elements affects the properties of the steel. 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. Heating in the presence of carbon or nitrogen-rich materials is used to form а hard surface on steel (case-hardening). High-speed steels, which are extremely important in machine-tools, contain chromium and tungsten plus smaller amounts of vanadium, molybdenum and other metals.
Вариант 8.
1. Перепишите следующие предложения, вставьте артикли там, где необходимо и переведите предложения на русский язык.
a) My friend’s name is... John.
b). . . Thames is... largest river of Great Britain.
c) We live on... third floor.
d)What... small girl!
2. Образуйте множественное число существительных.
Strawberry, photo, person, law, wife, book, potato, roof, dress
3. Перепишите предложения. Определите видовременные формы глаголов. Укажите их инфинитив и переведите предложения на русский язык.
a) They made great discoveries in the field of Physics and Chemistry.
b)I usually wash my face and hands with cold water.
c) Some of them will go to Brighton one of these days.
4. Перепишите следующие предложения, поставив прилагательные в скобках в нужную степень, и переведите предложения на русский язык.
a) Lena is the (good) student in the group.
b)This seat is the (comfortable) in the theatre.
c) This flower is (beautiful) than that one.
5. Прочитайте и переведите текст.
«Mechanical Properties of Matеrials»
Density (specific weight) is the amount of mаss in а unit volume. It is measured in kilograms per cubic metre. The density of wаtеr is 1000 kg/ m3 but most materials have а higher density and sink in water. Aluminium alloys, with typical densities around 2800 kg/m3 аге considerably less dense than steels, which have typical densities around 7800 kg/m3. .Density is important in any application where the material must not be heavy.
Stiffness (rigidity) is а measure of the resistance to deformation such as stretching or bending. The Young modulus is а measure of the resistance to simple sketching or compression. It is the ratio of the applied force per unit area (stress) to the fractional elastic deformation (strain). Stiffness is important when а rigid structure is to be made.
Strength is the force per unit area (stress) that а material can support without failing. The units are the same as those of stiffness, MN/m2, but in this case the deformation is irreversible. The yield strength is the stress at which а material first deforms plastically. For а metal the yield strength may be less than the fracture strength, which is the stress at which it breaks. Many materials have а higher strength in compression than in tension.
Ductility is the ability of а material to deform without breaking. One of the great advantages of metals is their ability to be formed into the shape that is needed, such as car body parts. Materials that are not ductile are brittle. Ductile materials can absorb energy by deformation but brittle materials cannot.
Вариант 9.
1. Перепишите следующие предложения, вставьте артикли там, где необходимо и переведите предложения на русский язык.
a) … Severn is the longest river.
b) He lives in … Lenin Street.
c) I usually have. . . breakfast at 6.30 a. m.
d) There is... interesting book on the table.
2. Образуйте множественное число существительных.
Shelf, life, fly, life, match, toy, tooth, piano, child
3. Перепишите предложения. Определите видовременные формы глаголов. Укажите их инфинитив и переведите предложения на русский язык.
a) She will be able to do the job on time.
b) Helen gives private lessons.
c) My friend heard the noise of a car.
4. Перепишите следующие предложения, поставив прилагательные в скобках в нужную степень, и переведите предложения на русский язык.
a) Sergey is (tall) than Andrew.
b)This text is the (difficult) in the book.
c) America is (large) than Australia.
5. Прочитайте и переведите текст.
The latest computer scourges, and their consequences
Those who use the Internet are unlikely to be seeing the headline above for the first time. In late August, a computer virus known as SoBig. F sent out millions of e-mails with that and other vague but enticing subject lines. Those unfortunates who opened the attachment to these e-mails will have had their machines infected by the virus, which will then have used their machines as platforms to spread the epidemic further.
At the peak of the epidemic, on August 19th, SoBig. F was responsible for one out of every 16 e-mails that crossed the net. A few days beforehand, a worm called Blaster had taken control of hundreds of thousands of computers. (A worm is a program that is similar to a virus, but does not require a user to open anything in order for it to propagate.) Blaster's purpose was to mount a so-called distributed denial-of-service (DDOS) attack on a Microsoft website. A DDOS attack works by overwhelming the computer controlling a particular network by bombarding it with messages. Microsoft was able to deal with the threat by changing the address of the website before the scheduled attack time.
SoBig. F's ultimate objective remains unknown—infected computers were meant to download a program from one of 20 pre-selected computers on the Internet. However, pre-emptive action by America's Federal Bureau of Investigation prevented the author of the virus from loading his instructions on to those computers in the first place.
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