1. How long you (to wait) for me? 2. I (to know) her since my childhood. 3. He (to think) about it for three days. 4. They always (to prefer) theatre to TV. 5. How long she (to study) music? - Oh, she (to study) music since her early childhood. 6. Since she was a little girl she (to try) not to take things seriously. 7. The students (to write) their test for two hours already. 8. She (to live) in that house round the corner about thirty years. 9. You (to play) too long. It’s high time to do your lessons. 10. She (to be ill) for more than two weeks. I (to miss) her terribly.

Learning foreign languages is important nowadays. I think that any educated person must learn foreign languages. But I prefer English to other foreign languages. Why? English is becoming a global language. A half of billion people in the world use English at home or work. English is the language which is known for the most part of our fine, magnificent and surprising world. English is so widespread that it has become the standard language for all kinds of international communication.

English is a universal language (global language in case we are not the only creature who can speak.) The world has changed. We can no longer live alone in our country anymore. If you want to learn the world you need to learn english
With IT, we can open ourselves to the world and the only way we can connect to the world is to the unviersal language.
If you are a business man you would have to learn english to expand your business to oversea.
If you are a students you would have to learn english for your own bright future or, at least, pass the exam.
If you are an employee you would have to learn english for the benefit of your career.
Even if you are just a street walker you still want to learn english to understand what's going on in the world
No matter who you are. Learn English is very important. You can't avoid it and do not avoid it before you getting too far behind.

1)Building materials are divided into natural (natural) and artificial(Строительные материалы разделяют на природные (естественные) и искусственные)

2)Не смогу сказать.

3)metals are divided into two groups: ferrous and non-ferrous(металлы делятся на две группы: черные и цветные)

4)Ferrous metals are those that contain steel and iron.Non-ferrous metals do not contain steel or iron. This group of metals includes: aluminum and copper, Nickel and lead, zinc and tin, brass and gold, silver and platinum, as well as many others that do not contain iron.(Чёрными называются те металлы, которые содержат сталь и железо.Цветные металлы не содержат стали и железа. К данной группе металлов относятся: алюминий и медь, никель и свинец, цинк и олово, латунь и золото, серебро и платина, а так же многие другие, не содержащие железо.)