Answer:
Hamlet’s behavior with Rosencrantz and Guildenstern has changed from being civil and friendly in Act II to being hostile and contemptuous in Act IV. In Act II, Hamlet welcomes his old school friends and reminds them of their "ever-preserved love". He also confides in them about his “distemper” and asks them to help him find out the cause of his father’s death. However, he also suspects that they have been sent by Claudius and Gertrude to spy on him, and warns them that he has "an eye of you".
In Act IV, Hamlet is no longer polite or trusting with Rosencrantz and Guildenstern. He accuses them of being sponges that soak up the king’s favors and commands, and tells them that they will be squeezed dry when the king no longer needs them. He also calls them “wretched, rash, intruding fools” who deserve to die for meddling in his affairs. He shows no remorse for altering the letters that order their execution in England, saying that they made a “bargain” with their lives.
When Hamlet calls Rosencrantz a sponge, he means that Rosencrantz is a servile flatterer who absorbs whatever the king says or does without any independent thought or loyalty. He also implies that Rosencrantz is easily manipulated and disposable, as a sponge can be wrung out or thrown away at any time.
Step-by-step explanation: