Riverside County and San Bernardino County to the north form this metro area. Like many such metro areas in the Southwest, it extends far into uninhabited desert areas, in this case east through the Mojave Desert to the Nevada/Arizona border. Larger than nine U.S. states, it is often referred to as the Inland Empire.
I agree with tchrist that the word doctor in doctor appointment is a noun (attributive noun I believe), although the definition of an attributive noun is a noun used as an adjective, so maybe it's just semantics at some point.
Which and That. This is one of the most common mistakes out there, and understandably so. âThatâ is a restrictive pronoun. Itâs vital to the noun to which itâs referring. e.g., I donât trust fruits and vegetables that arenât organic. Here, Iâm referring to all non-organic fruits or vegetables.