Answer: The speaker would spend years, decades and even centuries courting his mistress, if he had enough time.
Step-by-step explanation:
If he had enough time, the speaker of "To His Coy Mistress" would sit with his "coy mistress" for hours before deciding where they are going for a walk. He would try to get her attention for a decade, while she could ignore him for as long as she desires. He would take centuries to appreciate her body and face. He would be ready to wait for her love as long as it takes. If he had enough time, the speaker would spend decades and even centuries courting the mistress. However, as he argues in stanza 2, he does not have that amount of time to get her attention.