Lady Macbeth tells Macbeth to look like a flower on his face and a snake under his heart.Macbeth reminds Lady Macbeth to conceal her true feelings in front of guests.Macbeth seems to be brave on the face of it but he is mentally disturbed scorpions in his mind".And Macbeth says that by killing Banquo they have"scorched the snake,not killed it" meaning that Banquo is killed but Fleance is still alive.