Don't worry. The traffic is very heavy at this hour.
别担心。这个时间交通很拥挤。
So many countries, so many customs.
一个国家有一个国家的风俗。
Apparently what happened was that water collected on these tar pits, and the bigger animals like the elephants ventured out on to the apparently firm surface to drink, and were promptly bogged in the tar.