Task 4. Choose one of these modal verbs from the box to complete the sentences. There is one EXTRA verb.
may
should
must
could
can
need
1. When I was a little girl, I
do acrobatic tricks, but now I can't.
2. If there is not going to be any information about those passengers till tomorrow
morning, we call the police
3. Conflicts
lead to bad relations.
4. We have respect for other people,
5. Do you know that cats see in the dark?​

Dear Nick, Thank you for your letter. It was great to hear from you again. I guess I should start by telling you about meeting new people. First of all, you can make friends with somebody in your new class. Another way to make new friends is to join any clubs. It wasn't easy for me to get over my shyness, but you should try. I'm sure you'll succeed. By the way, how many lessons do you have in your new school? Is your new school far from your house? Do you like your new school? I've got to go now as I have to do my homework. Drop me a letter when you can. Take care, <Твоё имя>

If we would reduce the amount of rubbish we throw away, it would help the environment.
If we will recycle glass, paper, plastic, it will lead to fewer tress being cut down to make paper.
If we will produce a huge amount of rubbish each year, landfill sites will be full. 
If we paid more attention to nature, the Earth would be more green. 
The Earth would be cleaner if we would throw our rubbish into bins.
If we would use bicycles and not cars, air would be cleaner.
If we would make a lot of programmes about nature protection, alot of people would be more polite with nature.
If we won't look after trees, we would destroy the environment.