英文: I am very optimistic.
中文: 我很乐观。英文: Are you an optimistic person?
中文: 测测看你是一个乐观的人吗?英文: He might be overly optimistic.
中文: (或许老爷子太乐观了。英文: Keep optimistic regardless every adversity.
中文: 虽然事与愿违,但保持乐观。英文: My optimistic predictions came true.
中文: 我的乐观的预言成了现实。