Help напишите мини сочинение или рассказ используя вместе времена present perfect и present perfect continuous

We have been preparing for our exam since morning. But it's still so hard to understand questions.He has been reading the book for three hours.I have been waiting for him for several hours. He must explain me the topic. He has been explaining me the topic for a 30 minutes. Now I'm understanding this theme.

Мы готовились к экзамену с утра. Но это все еще так сложно понять. Он читал книгу три часа. Я ждал его несколько часов. Он должен объяснить эту тему. Он объясняет эту тему в течение 30 минут. Теперь я понимаю эту тему.

Dear, 
mother,
Thank you for letter. I'm fine here. Look at the picture. This is my new friend Diana. Every day we are went to the river, ate ice cream, helped grandma and grandpa, drew pictures, sang songs and played hide and seek. Natura very beautiful, the air is clean. I'm waiting for you to visit.
Best wishes,
(Твоё Имя).
Перевод:
Дорогая,
мама,
за твоё письмо. У меня всё хорошо. Посмотри на картинку. Это моя новая подруга Диана. Каждый день мы ходили на речку, если мороженное бабушке с дедушкой, рисовали картины, пели песни и играли в прядки. Природа очень красивая, воздух чистый. Жду тебя в гости.
С наилучшими пожеланиями,
(Твоё имя) 

The doctor will examine you carefully: feel your pulse, sound your chest, heart and lungs, test your blood pressure. The only thing you should do is to follow his directions. Otherwise a slight ailment can develop into an incurable malady.Is there anything more important than health? I rather doubt it. If your body suffers from any disorder your mind suffers with the body, too. You can't be good either at work or at studies. Aches and pains lead to irritation, nervous breakdown, exhaustion and apathy.
Doctors treat patients. If you have a headache, toothache, backache, stomach-ache or earache, if you have a sore throat, eye or finger, if you feel pain in any part of your body, if it hurts you to move — you need help. First of all you have to turn to your physician.
My friend Ann had a terrible toothache, so she made an appointment to see the dentist. He had a look at the tooth and decided that she needed a filling. The cavity was a big one, so he had an injection first. Afterwards it felt so much better