These trees have helped to prevent the great winds from sweeping through the city.
2
说不定哪一天一阵大风刮过,就可能把它吹倒。
Any day a strong wind might blow it over.
3
然而,当雪下过一段时候后,或者经过大风刮过时,雪会变硬变平,因此,雪表面将有助于音波传递。
However, snow can become hard and flat as it becomes older or if there have been strong winds. Then the snow's surface will help to send back sound waves.