proximity of zero order

例句：

1. 1. The two countriesare close to each other in terms ofgeography.
   这两个国家在地理上非常接近。
2. 2. The proximities of thestars are so vast that they can't be seen from Earth.
   星星的接近度如此之大，以至于从地球无法看见它们。
3. 3. The proximity of the two citieshas led to a significant increase in tourism.
   两个城市的接近导致了旅游业的显著增长。