forever is an adverb that is used to express a great length of time.
it is used to describe or reference a length of time that will seemingly persist or continue without end. For example, saying 'I will love you forever' suggests that the speaker will never cease to have strong feelings of love toward the recipient. The word can be also be used to refer to a state or condition that continues unendingly or eternally. For example, 'She will forever be remembered for her bravery and courage.'
1. We stayed up talking forever.
2. He will remember this day forever.
3. They've been together forever.
It is important to remember that even though forever can be used to suggest a great length of time, there still needs to be a point of reference to understand the length of 'forever'. Without one, the meaning of 'forever' can become ambiguous. For example, 'We listened to music forever' may imply that the listening session was quite long or possibly even never-ending. It is important to provide a time frame to give a better indication of duration. Additionally, 'forever' is often used as a hyperbole and should not be taken literally.