, Write the letter refusing the invitation. Use the example in WB ex. 21, p. 51and the plan in WB ex. 22, p. 51.

A,an неопределенные артикли. "А" ставится перед согласными, "an" перед гласными. Они исчисляемые и употребляются в един числе. Они употребляются после слова как:that is a, this is , Such a, quite, rather и еще после прилогательных a red flower и тд, после глагола to be например He is a student, she is a doctor и тд, и когда человек имеет ввиду значение "один" например wait a (one) minute подожди (одну )минуту. А еще в значении "any" то есть "любой".
The это определенный артиклю, он исчисляем и не исчисляем и используется как и во множ числе так и в един числе. Они используется в случае: 1) Если предмет один во всем мире (the sun, the sky, the galaxy) 2) до substantivided adj (the poor(бедняк)) 3) до таких слов как( radio, police, cinema, theater) 4) до порядковый числ, до прилагательных в сравнительной степени5) перед музыкальными инструментами
6) перед именами национальности ( I'm kazakh(я казашка))

On the downside can be attributed, and I think you will agree with me advertising. Advertising is a big minus commercial breaks rummage exciting movies, interesting programs, and sometimes, it seems that this short stretches of the film or television broadcast interrupt the endless advertising. And the biggest drawback of advertising - this is what ads show to anybody unnecessary items, as a good product does not need this kind of advertising, advertise it, those who use it. Yes, the very first and the biggest minus television - advertising. I sometimes think, why not create a separate channel by which all time would show one ad. All other channels are not free of it. A second disadvantage, in my opinion, are the TV series that flooded most of the time all the airtime. Series are disadvantages because they are all the same, and do not learn anything new, just pouring water. The advantages, that is an advantage, can be attributed TV news program, through which a person is informed about the situation in the world and in their own country. Another advantage - it's movies, especially movies with a deep sense and good performance of the actors. Such a film can for a lot in our lives to open their eyes and learn a lot. Well, of course, there is another advantage of television, such as educational and entertaining television programs, which give opportunity to relax and learn something new and interesting.
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