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The weight of the
planets was calculated by Newton as a young man.
The concept of relativity was proposed by Albert Einstein in 1905.
Most Cambridge colleges were found as schools of theology but in 1750 under the influence of Sir Isaak Newton, mathematics became compulsory and the main subject of study.
The first motor car was made in 1875 by an Austrian Siegfried Marcus. He used the internal combustion engine, which was perfected gradually.
The earliest motor cars were built like horse carriages and an early British company was called the Greatest Horseless Carriage Company.
The Rolls-Royce motor car was long known  as the best car in the world.
Water was discovered under the Sakhara Desert.
Diamonds were found in South Africa in the 19th century.
The electric battery was invented by Luigi Galvan in 1786.
The craters on the moon were caused probably by meteors.
Gold, silver and copper are valued for their luster.

1. He was with A young girl.This girl was A student of OUr Academy.2.This is A pencil. THE Pencil is red.3.She is A teacher. She is our teacher of English.4.It is A lake. This lake is deep. It's one of THE deepest lakes inTHE  world.5.There are many flowers in your garden. THE Flowers in your garden are beautiful.6.Did you write A plaN? Give me your plaN,please.7. THE Black Sea is in THE South of Russia.8.This is Nick. He works as AN engineer. He is A good engineer.9.There are some schools in ouR street. THE Schools Are new.10.Yuri Gagarin was THE first cosmonaut in THE world.11.In summer THE sky is blue and THE sun shines brightly.12. THE Petrovs are very friendly.13.This is Ann's book. I don't like such  book.14. Winter begins in December.