Complex sentence: The Phantom was replaced by the Phantom II in 1929; the designation Phantom I was never used by Rolls-Royce; it is a construct of enthusiasts applied to help distinguish it from other generations with the same model name.
Split into simpler sentences: The Phantom was replaced by the Phantom II in 1929. The designation Phantom I was never used by Rolls-Royce; it is a construct of enthusiasts applied to help distinguish it from other generations with the same model name.