This is from a song lyric > If a picture paints a thousand words, Then why can't I paint you? The words will never show the you I've come to know. If a face could launch a thousand ships, Then where am I to go? There's no one home but you, You're all that's left me too. And when my love for life is running dry, You come and pour yourself on me. First the singer says *If a picture paints a thousand words*. Followed by, *If a face could launch a thousand ships*. Why does the singer sing "If a face could launch a thousand ships"? Why not, "If a face can launch a thousand ships"? Why is _can_ used in the past?