Dr JM Chen, PhD Apr 3, 2010:

I agree 一不做，二不休 近义词： 破釜沉舟 反义词： 犹豫不决 用法： 复句式；作主语、分句；形容下最后的决心 解释： 原意是要么不做，做了就索兴做到底。指事情既然做了开头，就索兴做到底。 出处： 唐・赵元一《奉天录》第四卷：“光晟临死而言曰：‘传语后人，第一莫作，第二莫休。’” 例子： 到这地步，～，我是打算拼一拼了。（茅盾《子夜》七）.....

I agree with Shirley's 'to carry the thing through, whatever the consequences; to stick it out; to do something by hook or by brook...', the other options are as below:

# One may as well be hanged for a sheep as a lamb.
''.'一不做'.''''.'，'.''''.'二不休'.''。

# Whatever I do,I will do in my power.
''.'一不做'.''''.'，'.''''.'二不休'.''。

# In for a penny, in for a pound.
[谚]''.'一不做'.''''.'二不休'.''。

Shirley Lao Apr 3, 2010:

I think you should be asking "一不做，二不休" instead of "一不做, 而不休".

http://hk.dictionary.yahoo.com/search.html?s=�@�����A�G����