What warning does the nurse give Romeo?

The Nurse warns Romeo to not trick Juliet into thinking that he loves her more than he actually does. This action is in line with her usual behavior, for she always acts in the interests of Juliet throughout the play. This is because the Nurse is shown to have been Juliet's primary caregiver from the very beginning of her life, even rivaling and perhaps surpassing Juliet's mother in terms of influence. Evidence supporting this perspective can be found in Act 1, Scene 3, where Lady Capulet initial dismisses the Nurse so that she may speak to her daughter alone, only to quickly change her mind and request that the Nurse stay and provide counsel. This behavior indicates that the Nurse is valued by Lady Capulet and Juliet as a source of wisdom, and the Nurse clearly understands her influence as shown in her warning to Romeo. The Nurse wants the best for Juliet, and before she facilitates Juliet's relationship with Romeo, she must first ascertain that Romeo's intentions are pure.