3. Choose the correct answers. The light bulb
What would we do without electric lights? In the 1800s, light bulbs ' _by
different people, but none of them were good enough to sell until the right
material to go inside the bulb?
— Thomas Edison. Since then, electric lights
- around the world by billions of people.
The original designº— much, although more energy-efficient light bulbs
now in many parts of the world. However, in some countries, people can't
afford to use electricity. This fact encouraged U.S. teenager Ann Makosinski
to invent a new kind of light. This light ® __by electricity. It uses body heat
instead. But '_replaced by this new invention in the future? Probably not, but
light — and so this invention could definitely become popular in many parts
of the world.

1. a) are developed b) developed c) were developed d) is develop
2. a) were discovered by b) was discovered c) was discovered by d) were discovered
3. a) have used b) have been used c) have be used d) have use
4. a) isn't changed b) won't change c) hasn't been changed d) hasn't be changed
5. a) will be bought b) is bought c)are bought d) were bought
6. a) isn't powered b) wasn't powered c) hasn't powered
d) not powered
7. a) will be the light bulb b) will the light bulb be c) will the light bulb d) the light bulb
8. a) will be always needed b) always will be needed с) will be needed always d) will always be needed​

Объяснение:

North Carolina is the place I would like to go in the world. I have been there before and would like to go again. We stayed at a house that had a pool and a hot tub. It also had a game room and two bunk beds. My favorite football team is the Carolina Panthers. In North Carolina, I like to go to the beach. I would want to get there in a private plane jet. The jet service would get me there fast. I would want a couch in it with a TV and a little table. That's where I would travel to, if I could go anywhere.

Task 1.

1. Amy is sending an email to Jim at the moment.

2. Now my mum is checking emails.

3. Every week Sidney runs in a race. (Present Simple, потому что в предложение есть слово-маркер "every week", который относится к Present Simple)

Task 2.

1. I have written a long document.

2. Have you bought a new football ball?

3. Has Mary ever visited the Tower of London?

4. Has Bob sent an email to Pete?

5. Jim has already cleaned the flat.

6. Harry has just caught a big fish.

Task 3.

1. We were drinking tea when my friend called me.

2. Was she having a cup of tea at 7 in the morning?

3. When I was writing my report, Mark came to the office.

4. Did Nick and Helen phone their friend while we were watching TV?

5. He was walking home when somebody called his name.

6. Did the birds sing in the forest last spring?

7. Was Millie washing her T-shirt from 6 to 7 yesterday?

Task 4.

1. He’s a bit hungry. – I will make a sandwich for him.

2. She can’t use this computer. – My friend will show her.

3. They have no money. – They won't start their business.

4. We are going to repair the children’s room. Sorry, we won't come to see you this weekend.

5. When will the play start?

6. I think Sam won't visit us soon. He’s very busy.

7. Will they buy a new house in 2 years?