Answer:
Soon after he achieves the title Thane of Cawdor as predicted by the three witches; whom drive Macbeth’s ambition to murder King Duncan- due to the fulfilment of the witches’ first prophecy, Macbeth is foolish enough to commit to treason and murder King Duncan.
Answer: the boy has teased the girl
Hope this helps you:)
To reassure listeners.
The expression "Make very certain that this form of treachery shall never endanger us again" gives assurance to the listeners that such an incident will never be repeated or allowed in the future. The words "certain," and "never again" are strong expressions of finality -- that something must be stopped.