No, thank you. It's too late. I really have to go.
不,谢谢。太晚了,我真的该走了。
Yesterday will not be called again.
光阴一去不复返。
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.