1.27 Look at the house plan and listen. Then practise the dialogue with a partner.
Stacey What's wrong?
Danny I can't find my laptop.
Stacey Is it under the table in the living
room?
Danny No, it isn't.
Stacey Look, here's a laptop! Is this what
you're looking for?
Danny No, that's the wrong one.
Stacey What about the bedroom? Is it in the
wardrobe?
Danny No, it isn't. Oh, here it is! It's on the
bed.​

australia, or the commonwealth of australia, as it is officially called, is situated on the island continent. it also occupies the island of tasmania and some minor islands round the coast of the continent.

it is a highly developed industrial-agrarian country. its area is about 8 million km2. it is the only state in the world that occupies the territory of a whole continent.

the capital of australia is canberra, which became the capital only in 1927.

from 1787 to 1867 australia was a place where criminals were sent from britain. that is why the official language of australia is english.

almost one half of australian territory is occupied by deserts and semideserts. for quite a long period of time it was thought to be useless for economic development. but it is rich in coal, iron ore, bauxites, uranium, lead and many other mineral resources.

for almost a century the production and export of sheep wool was the basis of the economy of the country. now the most important industries are oil, chemical, ore mining, radioelectronics, and food industry. the country exports agricultural products and raw materials.

as for the nature, the commonest trees of australia are the eucalyptus and the australian acacia or mimosa, the national emblem of the country. such unusual animals as a kangaroo or a koala-bear originate from australia.

australia is one of the most unusual and exotic countries of the world. a significant feature of modern australian society is the representation of a lot of cultures drawn from many lands by its people.

historically part of the british empire and now a member of a commonwealth of nations, it is a relatively prosperous and independent nation.

Plastics are non-metallic, synthetic, carbon-based materials. They can be moulded, shaped, or extruded into flexible sheets, films, or fibres. Plastics are synthetic polymers. Polymers consist of long-chain molecules made of large numbers of identical small molecules (monomers). The chemical nature of a plastic is defined by the monomer (repeating unit) that makes up the chain of the polymer. Polyethene is a polyolefin; its monomer unit is ethene (formerly called ethylene). Other categories are acrylics (such as polymethylmethacrylate), styrenes (such as polystyrene), vinys (such as polyvinyl chloride (PVC)), polyesters, polyurethanes, polyamides (such as nylons), polyethers, acetals, phenolics, cellulosics, and amino resins. The molecules can be either natural — like cellulose, wax, and natural rubber — or synthetic — in polyethene and nylon. In co-polymers, more than one monomer is used.The giant molecules of which polymers consist may be linear, branched, or cross-linked, depending on the plastic. Linear and branched molecules are thermoplastic (soften when heated), whereas cross-linked molecules are thermosetting (harden when heated).Most plastics are synthesized from organic chemicals or from natural gas or coal. Plastics are light-weight compared to metals and are good electrical insulators. The best insulators now are epoxy resins and teflon. Teflon or polytetrafluoroethene (PTFE) was first made in 1938 and was produced commercially in 1950.Plastics can be classified into several broad types.1. Thermoplastics soften on heating, then harden again when cooled. Thermoplastic molecules are also coiled and because of this they are flexible and easily stretched.Typical example of thermoplastics is polystyrene. Polystyrene resins are characterized by high resistance to chemical and mechanical stresses at low temperatures and by very low absorption of water. These properties make the polystyrenes especially suitable for radio-frequency insulation and for parts used at low temperatures in refrigerators and in airplanes. PET (polyethene terephthalate) is a transparent thermoplastic used for soft-drinks bottles. Thermoplastics are also viscoelastic, that is, they flow (creep) under stress. Examples are polythene, polystyrene andPVC.2. Thermosetting plastics (thermosets) do not soften when heated, and with strong heating they decompose. In most thermosets final cross-linking, which fixes the molecules, takes place after the plastic has already been formed.Thermosetting plastics have a higher density than thermoplastics. They are less flexible, more difficult to stretch, and are less subjected to creep. Examples of thermosetting plastics include urea-formaldehyde or polyurethane and epoxy resins, most polyesters, and phenolic polymers such as phenol-formaldehyde resin.3. Elastomers are similar to thermoplastics but have sufficient cross-linking between molecules to prevent stretching and creep.

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