Final answer:
The provided excerpt does not include lines from Romeo and Juliet, so it's not possible to identify the foreshadowing within it. However, foreshadowing is found in the Prologue and in lines spoken by both Romeo and Juliet in the play.
Step-by-step explanation:
The question is asking to identify which two lines from Shakespeare's Romeo and Juliet foreshadow the tragic end of the titular characters. Unfortunately, the provided excerpt does not seem to include lines from Romeo and Juliet itself. Therefore, it's not possible to pinpoint the specific lines of foreshadowing within the given excerpt. To find examples of foreshadowing in Romeo and Juliet, one could instead look at lines such as the Prologue where it refers to "A pair of star-cross'd lovers take their life." - this directly hints at the tragic fate awaiting Romeo and Juliet. Other instances are when Juliet says, "My grave is like to be my wedding bed" (Act I, Scene V) and when Romeo says, "My mind misgives some consequence yet hanging in the stars...By some vile forfeit of untimely death" (Act I, Scene IV).