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_______there is fresh air, there is oxygen.
A．Wherever
B．Whenever
C．Unless
D．Whether
B．Whenever
C．Unless
D．Whether
参考答案
参考解析
解析：考查地点状语从句。句意为“凡是有空气的地方，就有氧气”。这里wherever表示无论哪里的意思，其他选项都不符合逻辑。
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