英语播客 A Cup of English 21 Water for Africa - analysis time

Scientists say the notoriously dry continent of Africa is sitting on(1) a vast reservoir of groundwater. They say that the total volume of water in aquifers underground is 100 times the amount found on the surface. The British Geological Survey and the University College London team has produced the most detailed map yet(2) of the scale and potential of this hidden resource. Across Africa more than 300 million people are said to (3) not have access to safe drinking water, and the demand is growing because of population growth and the need for agriculture. "Where there is the greatest ground water storage is in northern Africa, in Libya, Algeria and Chad," said Helen Bonsor from the BGS. In fact, according to the studies, there are aquifers even across sub-Saharan Africa. Water, over many years, can collect in the spaces between rocks underground, and even in the tiny spaces inside sandstone. This watery, wet stone area is an aquifer. The water found in these reserves(4) is usually cleaner than surface water. These huge bodies of water are equivalent to(5) a quarter of the Mediterranean Sea, or three times the Red Sea. The British experts caution (6) that drilling for water should be done carefully, and with a lot more research. The UK's secretary of state for international development, Andrew Mitchell said, "This is an important discovery which the British Government has funded, and could have a profound effect on some of the world's poorest people, helping them become less vulnerable."(7)
1. 'To sit on' can be used to say "He sits on the chair", but it can also be used figuratively with words like 'a fortune' or 'a time bomb'.
a. That boy comes from an extremely wealthy family; he's sitting on a fortune, and doesn't even know it.
b. That situation is like sitting on a time bomb; any day disaster can strike.
2. 'Yet' can be used in many instances. In this particular case, it means 'so far'. Here are 2 similar examples:
a. I have had fifteen job interviews, and the last one was the best one yet.
b. I have tried this new cookie recipe a few times, but this batch (collection of cookies) is the best one yet.
3. 'To be said (to)' can be followed by a positive or negative verb, or the verb 'to be' followed by an adjective.
a. The whole population is said to be musical.
b. Now, after the disaster, the ground, the river, and the plants are said to be radioactive.
4. 'A reserve' means a place where something is conserved, either naturally or deliberately.
a. Because the bird is so vulnerable, an island in the very south of New Zealand has been dedicated as a reserve for the kiwi.
b. Poland, apparently, has some of the biggest reserves of salt in the world.
5. 'Equivalent to' basically means 'equal to' or 'the same as'.
a. My son and his grandmother are equivalent in height.
b. The time we spend sleeping is equivalent to a quarter of our lives.
6. 'To caution' is a verb that means to warn. Note the difference in these two following sentences.
a. We cautioned him about driving fast.
b. We cautioned him that driving fast in icy weather would be a mistake.
7. 'Vulnerable' is another way of saying easily affected, weak, or exposed. The pronunciation is a bit tricky, as the 'l' isn't always silent.
a. He feels vulnerable without his glasses on.
b. Hopefully, as Africa utilizes its vast water reserves, its people will no longer be vulnerable to drought or famine.
 
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zie@�ont-family:Verdana'>b. I'm sure questions will be raised when the employees hear about him leaving the company.
6. 'Overwhelmingly' here is used as an adjective, but of course, it comes from the verb to 'to overwhelm'.
a. The votes show that she is overwhelmingly the most popular singer.
b. I was overwhelmed by your act of kindness.
7. 'Carbon footprint' is the amount of greenhouse gas emissions we cause on a personal level.
a. This year, I'm going to do all that I can to reduce my carbon footprint.
b. There are some simple ways to reduce our carbon footprints, like recycling, and turning off lights that don't need to be on.
8. 'Collaborative' comes from the verb to collaberate, meaning to work together and share ideas.
a. The project was a collaborative effort; many experts were involved.
b. If we collaborate, we will probably find the best solutions to our problems.