Как правильно написать + объяснение what you (do) here now? i (look) at the window. every day john (wind) his watch at 10 o"clock in the evening. lena usually (help) her mum. she (help) her mum since the morning. they already (wash) the floor and (dust) the furniture. this is a factory where my father (work). he (work) there for 10 years already. he just (receive) a message. where he (be)? he (work) in the garden now. he (work) there since breakfast. i (not/find) a book yet. i (look) for it for half an hour. i often (go) to the library and (borrow) new interesting books. she (write) a compositions for 2 hours already, but (not/finish) it yet. listen! my sister (sing) i (wait) for a letter from my cousin for a month, but (not/receive) it yet. every day i (go) for a walk to the park. my friend often (go) with me. you (play) with a ball for an hour. go home and do your homework. i (live) in st.peterburg. i (live) here for 10 years already. what you (do) here now? i (read) an article. i just (receive) a letter from my granny.

What are you doing here now? I  am looking at the window. (сейчас)
Every day John winds his watch at 10 o"clock in the evening. Lena usually helps her mum. (обычные действия)
She has been helping her mum since the morning. (известно, как долго длится процесс)
They have already washed the floor and dusted the furniture. (действие свершилось и есть результат)
This is a factory where my father works. (обычное действие)
He has been working there for 10 years already. (известно, как долго длится процесс) 
He has just received a message. (действие свершилось и есть результат)
Where is he? He is working in the garden now.  (сейчас)
He has been working there since breakfast. (известно, как долго длится процесс) 
I haven`t fond a book yet. (результат)
I have been looking for it for half an hour. (известно, как долго длится процесс) 
I often go to the library and borrow new interesting books. (обычное действие) 
She has been written a compositions for 2 hours already, but hasn`t finished it yet. (известно, как долго длится процесс; но результат не достигнут) 
Listen! My sister is singing.  (сейчас)
I have been waiting for a letter from my cousin for a month, but haven`t received it yet. (известно, как долго длится процесс; но результат не достигнут) 
Every day I go for a walk to the park. My friend often goes with me. (обычное действие) 
You have been playing with a ball for an hour. Go home and do your homework.
  (известно, как долго длится процесс)
I live in St.Peterburg. (обычное действие) 
I have been living here for 10 years already.  (известно, как долго длится процесс)
What are you doing here now? I reading an article. (сейчас)
I have just received a letter from my granny. (результат)