Please explain in detail about the last two lines of "Ode to the West Wind".I want to speak on it in my colloege. so please tell in detail.

"The trumpet of a prophecy!  O, Wind/

If Winter comes, can Spring be far behind?"

The closing lines of Shelley's "Ode to the West Wind" highlights several themes of Romanticism as well.  One explanation behind the last two lines is that it speaks of hope and optimism.  Shelley seems to be saying that the wind carries with it the belief that something better lies ahead.  For example, if one feels the wind in winter, one knows that spring is nearby.  Shelley is saying that the movement of the wind and its freedom bring with it a spirit of limitless freedom.  There is a sense of unlimited potential with this wind, and the "trumpet" that sounds is the sound that indicates while things might be difficult or bad, there is something else that might lie ahead which can be hopeful and optimistic.

When you read these two lines, remember that the first line sets up the second line.  It is this closing line that becomes very powerful for Shelley.  Some say that he wrote these lines in the wake of the death of his son, while others say he wrote to expres his hopeful vision for political revolutions.  If we take both ideas at face value, we see that the explanation of meaning for both of these lines is one of hope and progress, the idea that change can happen despite what might be in front of us.  We can change what is to what can be when we know that "spring" cannot be far behind.