She (to lear) many terms every day. 2) High performance of the car (to depend) on proper operation.. 3) Where she (to study) ? 4)Many new cars (to appear)

dis- mis- if- un-
1.comfortable-
2regular-
3.honest-
4.understanding-
5.friendly-

every day.

arteries to all the parts of the body Scientists have determined that the total weight of the blood pumped by the hemi daily is about 10 tons. Physiologists have established that in the adult the heart makes from 60 to 7,' beats per minute.4n children the rate of heartbeat is much higher. Research work of many scientists has helped to determine that the rate of heartbeat increase depending on different emotions. Each beat of the heart is followed by a period of rest for the cardiac muscle Each wave of contraction and a period of rest following it compose a cardiac cycle The period of rest is shorter during greater physical exertion and longer when the body is at rest. The physiologists called the first phase of short contraction of both atria - the atrial systole, the second phase of more prolonged contraction of both ventricles- the ventricular systole. The period of rest of the cardiac muscle is called the diastole The blood received by the left atrium from the pulmonary circulation is discharged out by the left ventricle to the systemic circulation through the aorta. The atria act as receiving chambers.

Вот текст:

Metals are materials most widely used in industry because of their properties. The study of the production and properties of metals is known as metallurgy.

The separation between the atoms in metals is small, so most metals are dense. The atoms are arranged regularly and can slide over each other. That is why metals are malleable (can be deformed and bent without fracture) and ductile (can be drawn into wire). Metals vary greatly in their properties. For example, lead is soft and can be bent by hand, while iron can only be worked by hammering at red heat.

The regular arrangement of atoms in metals gives them a crystalline structure. Irregular crystals are called grains. The properties of the metals depend on the size, shape, orientation, and composition of these grains. In general, a metal with small grains will be harder and stronger than one with coarse grains.

Heat treatment such as quenching, tempering, or annealing controls the nature of the grains and their size in the metal. Small amounts of other metals (less than 1 per cent) are often added to a pure metal. This is called alloying (легирование) and it changes the grain structure and properties of metals.

All metals can be formed by drawing, rolling, hammering and extrusion, but some require hot-working. Metals are subject to metal fatigue and to creep (the slow increase in length under stress) causing deformation and failure. Both effects are taken into account by engineers when designing, for example, airplanes, gas-turbines, and pressure vessels for high-temperature chemical processes. Metals can be worked using machine-tools such as lathe, milling machine, shaper and grinder.

The ways of working a metal depend on its properties. Many metals can be melted and cast in moulds, but special conditions are required for metals that react with air.