scarce → scarcity、scarcely

scarce a. 稀缺的
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scarcity [ˈskeəsəti]  n. 稀缺，短缺
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例：the scarcity of skilled workers 缺乏熟练工人
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scarcely ad. 几乎不
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例：Scarcely had I sat down to eat when the phone rang. 我刚坐下，电话铃就响了。（剑桥词典）