с упражнением. очень нужно(
Replace the adverbial clauses of time by the Participle. Model: When you speak English, pay attention to the intonation. (When Speaking English, pay attention to the intonation.
1. Be careful when you cross a street.
2. When you leave the room, don't forget to switch off the light.
3. When you begin to work with the dictionary, don't forget my instructions.
4. When they were travelling in Central Africa, the explorers met many wild animals.
5. When you copy English texts, pay attention to the articles.
6. You must have much practice when you are learning to speak a foreign language.

People have always polluted their surroundings. But until now pollution was not such a serious problem. People lived in uncrowned rural areas and did not have pollution - causing machines. With the development of crowded industrial cities which put huge amounts of pollutants into small areas, the problem has become more important. Automobiles and other new inventions make pollution steadily worse.

перевод:

Люди всегда загрязняли окружающую среду. Однако до последнего времени загрязнение не было такой серьезной проблемой. Люди жили в слабозаселенных сельскохозяйственных областях, у них не было загрязняющих природу машин. С развитием перенаселенных промышленных городов, в которых огромные количества отходов выбрасывались на маленькой площади, эта проблема стала гораздо серьезнее. Автомобили и другие новые изобретения делают загрязнение все интенсивнее.

Объяснение:

I like interesting and funny movies. A film is a personal work of cinema. Technologically, a film is a separate work of cinematography, a set of moving images (fragments) related to a single plot. I last read a book by Harry Potter. The main characters are an orphaned boy Harry, Hermione and Ron, students at the Hogwarts School of Magic. They met on the train to the magic school. At Hogwarts, they learn magic. I really liked this book. Very strong. I would recommend young readers to read this book.