Shadow boxing when I heard you on the radio [HUUUH!!!]
Shadowboxing is an exercise used in the training for combat sports, especially, as its name implies, in boxing. It is used mainly to prepare the muscles before the person training engages in stronger physical activity.
LL is preparing himself to lyrically beat the shit out of that wack rapper.
Or he could beat the shit out of him with his fists, like he did to that burglar that broke into his home
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