Task 3. Complete the sentences using the words in the box. You will need to use one word twice.
compression, deformation, elongation, extension, tension
1. A stretching force is called
2. A crushing force is called
3. Extension is also called
4. Tension causes .. or
5. Tension or compression cause
Task 4. Match the tivo parts to make correct sentences.
1. If a material is stiff
2. If a material is brittle
-
3. If a material is plastic
4. If a material yields
5. If a material fractures
6. If a material is elastically deformed ...
a) it is malleable and/or ductile.
b) it has low elasticity and low tensile strength.
c) it has low elasticity and high tensile strength.
d) it has been extended to a point before its elastic limit.
e) it has been loaded beyond its ultimate tensile strength.
1) it has been significantly plastically deformed, but not broken.​

The book is the greatest teacher of all mankind. This is a friend accompanying us from the nursery cradle to a very old age. The book that is in our hands is capable of giving us very much. But provided that we will also give her some of our attention and time. In the relationship with the book, the universal law of interchange and conservation of energy operates.

I like to read many novels from Russian literature. When you read books, like you are part of this book and part of its history. Reading a book is a mystery! The reader is immersed in his unique, individual world, uniting within his consciousness with the more subtle mental worlds of all mankind. This is an amazing phenomenon ...

Happy is the man who is friends with the book, and no, in my opinion, more unhappy than those who don't like to read. After reading the book - it is not easy to obitain any information that is an immersion into the world of fantasy huge number of very different and very talanted authors. And maybe not a fantasy, and most of these expriences, real travel and many others.
The book - a source of knowledge! How many interesting and incredible can learn from books: love, happiness, distant lands. A encyclopedias and dictionaries to answer even the most difficult question. 
The book - a wondeful way of entertainment. After all, there's nothing better a pleasant evening in the company of interesting books: novels, detective or someone's memoirs. Not so important that each of us loves what genre preference. The main thing - to read it and enjoy all these "shaped as letters" getting incomparable to anything fun.