Fat chance
不可能，沒門兒 是一種諷刺（sarcastically)的說法
A: Are you going to buy me a new coat for Christmas?
你會給我買件新外套當做圣誕節禮物嗎？
B：Fat chance!
沒門兒！
I think it's 50/50.
有一半的可能性
We have a 50/50 chance.
有一半的可能性
There is no hope.
幾乎不可能
There is no possibility.
幾乎不可能
There is no chance.
幾乎不可能

Chance
是一種偶然的機會
Opportunity
是一種被給予、被許可的機會。
I was never given the opportunity of going to college.
我從來都沒有機會上大學。
She left and I missed my chance to say goodbye to her
她走了，我錯過了跟她說再見的機會。
This is a good opportunity to get a promotion.
這是個升職的好機會。
This is a too good chance/opportunity to be lost.
這是個不容錯失的好機會。
Yes. It's my fault. So please give me a one more chance.
是我的錯，請再給我一次機會。