时逢18世纪，这一转变以棉纱生产新技术之形式来临。
These came in the 18th century in the form of new technologies in cotton production.
时逢盛夏，烈日当头，固执的母亲在烈日下一站就是几个小时。
Every summer, the scorching sun head, stubborn mother is the next stop in the scorching sun for several hours.
时逢夏日，冰川就会自然融化，顺着阿拉斯加湾冲刷出大量由微生物尸体构成的有机质。
Glaciers that naturally melt each summer along the Gulf of Alaska flushout huge amounts of organic material, made up mostly of dead microbes.
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