Answer:
The lines that foreshadow Tybalt’s death are:
1. Tybalt: "I will withdraw; but this intrusion shall / Now seeming sweet convert to bitter gall."
2. Mercutio: "More than prince of cats, I can tell you. O! [Tybalt] is the courageous captain of compliments."
These lines hint at Tybalt's aggressive nature and the brewing conflict, which eventually leads to his demise.