Written by Michael Nesmith of the Monkees. The Monkees were a band brought together for a TV series in 1966 and soon became creative artists in their own right. Michael Nesmith and Mickey Dolenz continue to tour as of 2019. The lyrics to the song are about a fellow wanting just to be with Mary. It is interesting to note that other songs written during that time often used the name Mary to represent Marijuana.
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