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来源:雅诚德英语网
The sun, is also variable over a long term: its heat output goes up and down in cycles, the latest trend being downward.
太阳在长期内也是变化的:它的热量输出在周期中有上升,也有下降,最近的趋势是下降。
The sun, is also variable over a long term: its heat output goes up and down in cycles, the latest trend being downward.
太阳在长期内也是变化的:它的热量输出在周期中有上升,也有下降,最近的趋势是下降。