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- 中纬度时现E层midlatitude sporedic E layer
- 在中纬度中和时现E层分子和金属离子的相对浓度Relative concentrations of molecular and metallic ions in midlatitude intermediate and sporadic-E layers
- 时现E层sporadic E layer
- 极光时现E层auroral sporadic E layer
- 中纬度时现Ｅ层mid-latitude sporadic E layer
- 赤道时现E层equatorial sporadic E layer
- 几时what time; when
- 薄层folium
- 报时give the correct time
- 折现realization
- 中间层mesosphere
- 必要时in a pinch
- 面层surface
- 折现率discount rate
- 时有occasionally; from time to time
- 图层layer
- 半时half
- 这块殖民地现已获得独立。The colony has now attained nationality.
- 膜层retia
- 1939年战争爆发时，她的父母在国外，他们直到战争结束时才能返家。Her parents were abroad when the balloon went up in1939 and they could not return home until the war was over.
