feasible、possible与practicable这些形容词均有“可行的”之意。
feasible : 指完全可行，切实可行，强调成功的较大可能性。
- With the extra resources, the project now seems feasible.
有了额外的资源，这个计划现在看来是可行的。 - It may be feasible to clone human beings, but is it ethical?
克隆人类也许可以做到，但是这合乎道德吗？
possible : 多用来消除对某事的怀疑，侧重从客观上看有存在或发生的可能。
- I can't get it all done by Friday - it's just not possible.
我星期五前无法全部完成——是不可能的。 - Is it possible to buy tickets in advance?
可以提前订票吗？ - They got as far as was humanly possible (= as far as anyone could have) before turning back.
他们折回来前已尽力能走多远就走多远了。
practicable : 强调经过证明是有效的，合乎实际，行得通的。
- The troops will be brought home as soon as practicable.
军队将尽快撤回。 - It is not practicable to complete the tunnel before the end of the year.
年底前这个隧道不可能竣工。
