Thomas Malthus published his "Essay on the Principle
of Population" almost 200 years ago. Ever since then,
forecasters have being warning that worldwide famine was S1_____
just around the next corner. The fast-growing population"s
demand for food, they warned, would soon exceed their S2_____
supply, leading to widespread food shortages and starvation.
But in reality, the world"s total grain harvest has risen
steadily over the years. Except for relative isolated trouble S3_____
spots like present-day Somalia, and occasional years of
good harvests, the world"s food crisis has remained just S4_____
around the corner. Most experts believe this can continue
even as if the population doubles by the mid-21st century, S5_____
although feeding I0 billion people will not be easy for
politics, economic and environmental reasons. Optimists S6_____
point to concrete examples of continued improvements
in yield. In Africa, by instance, improved seed, more S7_____
fertilizer and advanced growing practices have more than
double corn and wheat yields in an experiment. Elsewhere, S8_____
rice experts in the Philippines are producing a plant with few S9_____
stems and more seeds. There is no guarantee that plant
breeders can continue to develop new, higher-yielding crop,
but most researchers see their success to date as reason S10_____
for hope.
1. beingbeen have\has been doing
2. theirits population, they warned,its
3. relativerelatively 6
4. goodbad
5. as even if
6. politics—political
7. byfor for instanceStay focused on the prepositions!
8. doubledoubled double ed
9. fewfewer andmorefewerand
10. reason the reason thereason for hope thethe
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