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your european friend has invited you to come. write an e-mail about your arrival
using the information about the flight (ba516 from kyiv, july 5, 2005, arrives at
16.45, local time)

The experiment will be carrying out next week.
The book was written 10 years ago.
He has been asked a lot of questions.
All the documents has been left in the office.
A pupil is praised when he works hard.
He will be forgotten in a few years’ time.
This house was built last year.
His paper will be discussed tomorrow.
The conference has been opened.
All the texts has been typed.
The sound wasn`t heard. 
This picture is always admired. 
Возможно в некоторые предложения стоит добавить уточнения вроде "by people" или "by somebody". Это уже на ваше усмотрение. 

A galaxy is a large system of stars, interstellar gas, dust, dark matter and possibly dark energy, bound by the forces of gravitational interaction. The number of stars and sizes of galaxies can be different. As a rule, galaxies contain from several million to several trillions (1,000,000,000,000) stars. In addition to ordinary stars and the interstellar medium, galaxies also contain various nebulae. Dimensions of galaxies from several thousand to several hundred thousand light years. And the distance between galaxies reaches millions of light years.