English Grammar Question, someone who really knows this?

There is something called "poetic license" which a special leniency granted to poets and songwriters to break some grammar rules in order to make the words fit the rhythm of the song or the meter of the poem. In this case, PP&M chose to eliminate the word "will", as in "...will soon be over", so that the verse fit more closely with the rhythm of the song. There is a limit to poetic license, however...the verse still needs to be understandable....you might need to scratch your head over it for a second or two, but you should eventually be able to figure out the meaning. If you can't understand it at all, then the poet has overstepped his or her poetic license.