I would say that 1 and 2 suggest that you were watching her deliberatlely, but surreptitiously - that you want to watch her, but you don't want to be seen watching her. I would assume that 3 meant that you were looking at something else, and were not particularly interested in her , but that something she did caught your attention, causing you to notice her actions even though she wasn't the primary object of your attentions. Rommie
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