单词	F region
释义	F region noun : the highest region of the ionosphere occurring from 80 miles (130 kilometers) to more than 300 miles (500 kilometers) Word History First Known Use 1923, in the meaning defined above
随便看	midst midstories midstream midstreams midsts midsummer Midsummer Day Midsummer Eve midsummer madness midsummer night midsummers midsummery midterm midtermer midtermest midterms midtown midtowner midtownest midtowns Midvale midvein midwatch midwatches midway

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