The narrator of the poem is a man deeply in love, who beloved does not reciprocate his feelings and does not correspond to his sentiments. He compares the beauty of his beloved with the light of the day and the absence of her with the daybreak.
We all know about diaphragm but do we know what happens when we breathe in?
What do we know about the permeability of the cell membrane?
What is dark matter and how much do we know about it?