Well, you don't exactly comment per se. You click "answer" or go to someone else's answer and click reply (not sure the exact labelling but it's something along those lines).
Edit: It says "add your comment to this answer here", not "reply."
Answer:
ggggggggggggggggggggggggggggggggggggg
Explanation:
<span>C. animal
Yeats, in this poem, uses an animal (swans) to represent the way time passes and changes, and the natural beauty of that cycle. He sees the swans year after year but knows that one day, even the swans will disappear from the lake.</span>