Write full positive sentences in present perfect. 1. we already a tasty salad. (cook) 2. they a tree. (grow) 3. william a new flat. (buy)

1.a garbage is not only ugly, bute dangerous because it causes an air pollution.

2. cars are an important part of a life for most people. but cars also cause a pollution and release fume.

3. in canada people don't realise that they throw out 10,000 tons of a waste.

4. over 14 billion pounds of a waste per year is throw out to sea and it kills millions of sea animals.

5. if we want to breathe  a healthy air we have to think about what we do.

6. because of our lack of a knowledge there is now a huge hole over an antractic.

7.a water is a vital element of a life.

  how long have you been trying to find a job?

for three years. it was really difficult.

how many jobs have you had?  

about thirty, maybe more i have been doing everything.

how long have you been standing here today?  

i have  been waiting since 8: 00 this morning, and i'm freezing.