Zunhua is one of the famous tourism destinations,          lies Donling, a group of the Qing Imperial Tombs.

The children, ____ had played the whole day long, were worn out.

A turning point of the continuously high housing price won't appear suddenly because there must be a certain process _        many factors lead to the change．

You can take any seat _______ is free.

The Dead Sea is so salty ____ it’s hard for anything to live in it, ____ is why it’s called the
Dead Sea.

Mr. Smith has been to many famous cities in China, _______ Chengdu has impressed him most.