as (或 when 或 where) the fancy takes one

according to one's inclination

由兴趣主宰；由着性子；跟着感觉

you could move about as the fancy took you.

你可以随便四处走动。

fancy one's (或 someone's) chances

believe that one (or someone else) is likely to be successful

相信自己（或别人）会成功

we fancy our chances in the replay.

我们相信自己会在复赛中取胜。

take (或 catch) someone's fancy

appeal to someone

讨某人喜欢；迎合某人的口味；吸引某人

take a fancy

to become fond of, especially without an obvious reason

（尤指莫名其妙地）喜爱