Build your own telesccpe
if you 1___ (want) to see the stars and
planets, you 2 (can) make
your own tetescope. All you need is a
cardboard tube — the ones you 3___ (use) if you want to send
a poster by mail — and a couple of lenses,
Make sure you cut the tube very straight.
This is important, as you 4
(not be able to) change the focus unless
it 5 (be) absolutely straight.
Then attach the lenses inside the tube.
You can just slide them in, but if you 6 (need) to make them
secure, giue them in carefully. Finaiiy,
cover the other end of the tube with card
and make a small hoie In the end to look
through. Now you're ready to look at the
stars! It’s not the world's most powerful
telescope, but if you 7 (use) it
on a clear night, you get some good views
If i 8 (not have) mine,
I wouldn’t see so much of the night sky.
2. If we dump all sorts of chemicals into rivers, we will not be able to swim in them in the future.
3. If we do not stop cutting down so many trees, we will endanger our oxygen supply.
4. Soon the Earth’s resources will be exhausted if the human population continues to grow.
5. If everybody continues to use aerosols and CFCs, the hole in the ozone layer will get bigger.
6. If the sun radiation can’t escape into space, Earth’s temperature will increase steadily.
7. If the global temperature rises, sea levels will rise too.
8. We’ll threaten our own existence if we do not cut down on waste rapidly.
9. People will run out of drinking water one day if they do not use it more rationally.
10. If he wants to help the planet, then he has to change his habits
3. The girl is...at the table. 4. The man is...on the chair.
5. The book is...in the bag. 6. The pencil is...under/on the desk.
7. My house is ...in the street. 8. The blackboard is ...in the
classroom. 9. The chair is ...by/at the table. 10. We sit ...at the
table. 11. There is a lamp ...near/on the desk. 12. Please, sit
down ...at the table. 13. A sport ground is ...behind our school.
14. Pushkin street is ...between Lenin street and Sadovaya street.
15. We have lunch ...between 11 o'clock and 12 o'clock. 16. The
bridge is ...over/across the Don River.