When the relative pronoun is the object of a preposition, which is used instead of that, for example,  in which ,  for which ,  about which ,  through which , etc. (please see the third example below): Formal English: This is the man to whom I wanted to speak and whose name I had forgotten.he relative pronoun that can only be used in restrictive clauses. It can also be substituted for who (referring to persons) or which (referring to things) in informal English. Whereas that is often used while speaking, who and which are more common in formal written English.
For other uses, see Yellowstone (disambiguation). Yellowstone National Park is a national park located in the U.S. states of Wyoming, Montana and Idaho. It was established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872. Yellowstone was the first National Park in the U.S. and is also widely held to be the first national park in the world.
Yellowstone National Park is a national park in the United States. It was the known as the first national park in the world. It was created on March 1, 1872 when United States President Ulysses S. Grant signed a law to create it. The name was taken from the Yellowstone River, which flows through the park.Yellowstone was made a UNESCO World Heritage Site in 1978.ellowstone National Park is famous for its geysers and hot springs. The park contains about half the world's geysers. The world's most famous geyser, the Old Faithful Geyser, is in Yellowstone National Park.