阅读下面短文, 在空白处填入1个适当的单词或括号内单词的正确形式。
With the expanding of cities,
the (grow) of population and reduction of agricultural land cause a great
challenge to food supply. Planting hybrid rice is the most effective way
(increase) crop yield per unit area. "Father of Hybrid Rice" Yuan Longping
has made enormous (contribution) to the development of high-yielding
hybrid rice.
China is currently one of the
world's largest food producing countries. However, in the 1960s, when young
Yuan Longping witnessed the nation suffering severe food crisis—the destructive
3-year countrywide famine, he was stricken, (feel) sorry and determined to
develop high-yielding crops for farmers. (team) up with his colleagues, Professor
Yuan finally succeeded discovering natural male sterile plants,
served as the beginning of his research on hybrid rice. Today, nearly 57% of
rice field in China grow hybrid rice species and the increase in output can
support 70 million more people (annual).
Even when Professor Yuan was
in his eighties, he insisted on working on the rice field with an aim to
develop even-more high-yielding and (good) quality hybrid rice for
world food supply.
答案:【1】growth/growing【2】to increase【3】contributions【4】felt【5】Teaming【6】in【7】which【8】annually【9】an【10】better