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 (Arapaho: Henihco'oo or Heetihco'hÃ©etÃ­hco) oo is a national park located primarily in The.U. s state Of, wyoming although it also extends Into montana And. Idaho it was established by The.U. S congress and signed into law By President Ulysses. S grant On march, 1. 1872pproximately 96 percent of the land area of Yellowstone National Park is located within the state of Wyoming. Another three percent is within Montana, with the remaining one percent in Idaho. The park is 63 miles (101 km) north to south, and 54 miles (87 km) west to east by air.