Подчеркните инфинитив одной чертой, а герундий – двумя чертами. 1. I don’t think this product is worth advertising.
2. The amount to be paid includes the cost of packing.
3. Before leaving abroad Victor applied for the visa.

Summer is the best time of the year. I love it, because I have a vacation in the summer. In the summer I was with her parents at the sea. When the weather was sunny. I swim and sunbathe. I also went to the elder brother in Moscow. I'm not the first time in Moscow. But I always wonder, what is it a huge and beautiful. Boating on the river Voronezh, he fished. The reserve is visited Chervonyy Yar, where the animals walk not according to the aviary and free for the park area. He helped collect apricots and plums in the country. Where in the evening we had a bonfire. In general, the summer I did it!

Dear Anna,
 I'm so sorry that I can not come to your birthday party.  I'd love to visit you but unfortunately I'm ill. That's why I'm writing to you a letter.  I wish you to always  have  very good health and to be with reliable people around. Good luck to you!
Happy Birthday, my dear! 
I'd like  to apologize again for not congratulating you personally. But I promise you that I will visit you next time.
                                                                  Love you,
                                                    (Потпись на английском, Ваше имя) 
PS  Я немного видоизменила предложение "Хочу пожелать тебе  здоровья удачи и верных друзей!"
Я написала "Я желаю тебе всегда иметь хорошее здоровье и  быть вокруг (среди) надежных людей. Удачи тебе! С Днем Рождения, моя дорогая!"
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