Optim = best
* optimism
n. 乐观，乐观主义
He was still full of optimism for the future despite his many problems.
他尽管有许多问题，但对未来仍十分乐观。
* optimistic
a. 乐观的，有信心的
She's not optimistic about the outcome.
她对结果不很乐观。
* optimist
n. 乐观主义者
He's such an optimist that he's sure he'll soon find a job.
他很乐观，认为自己一定很快就能找到工作。

* pessimism
n. 悲观主义
There is a mood of pessimism in the company about future job prospects.
公司中有一种对未来职场前景悲观的情绪。
* pessimistic
a. 悲观的
a pessimistic view of the world
对世界的悲观主义看法
* pessimist
n. 悲观主义者
It's easy to sell insurance to a pessimist.
向悲观的人推销保险很容易。