A convivial atmosphere or occasion is friendly, pleasant, cheerful, and relaxed.
If someone is described as vivacious, they are lively and have a happy, lighthearted manner.
A vivid picture is brightly colored, intense, and/or lifelike.
If you survive something, such as a difficult time or trouble, you manage to make it through or live to tell of it.
Differentiated vocabulary for your students is just a click away.