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媒體英語會帶大家一起學(xué)習(xí) BBC 撰稿人在報道世界大事時常用到的單詞和短語。

最新的研究報告說，一戶普通美國人家的家中會隱藏著約九千種不同類型的微生物，這些微生物是怎么進(jìn)來的呢？以下是 Rebecca Morelle 的報道。

A genetic analysis revealed that the average household had more than 2,000 species of fungi. The types of fungus found though depended on the home's location, suggesting these minute organisms are drifting in from outside.

The researchers also discovered an average 7,000 different types of bacteria per household. But the species varied according to whether men or women were the main residents or whether they lived with cats or dogs.

Although the study was carried out in the US, the scientists say the findings are also relevant around the world.