5. Fill in the blanks with prepositions:
1. It is dangerous to go a stormy day. 2. Lightning is a very
great flash ... light resulting ... a discharge ... atmospheric
electricity. 3. Protecting buildings ... lightning was the first
discovery ... the field ... electricity used ... the good ... mankind.
4. ... thousands ... year’s people knew nothing ... thunderstorms.
5. Lightning flashes are followed ... thunder which can be heard
... kilometers around. 6. There is always some danger ... a
thunderstorm ... a very high building or a man standing ... the
open field. 7. It is difficult to see a single drop ... water ... the
sea. 8. Some scientists ... the past melted metals ... the help ...
solar furnaces. 9. Modern civilization cannot do... electrical
appliances. 10. Electric current is necessary ... the operation ...
trolley-buses, buses, and modern trains