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I won't take my eyes off you for a moment.
Literal
I [topic-は] one-moment-[emphatic-も] you [from-から] eye [object-を] let-go-not.
片時 ('a brief moment,' literally 'half-time'). 片時も~ない ('not even for a moment') uses the minimal-unit + も + negative pattern for total negation. 目を離す ('take one's eyes off, look away,' literally 'separate the eye'). A romantic or protective declaration.