without putting in some work? Not much.

Imagine it this way... bitcoin is like a big number guessing game. In each round (read: for each block) there are a number of "right answers" that everyone has to guess at. The faster your machine (which can be CPU (easy) or GPU (more work, requires hardware), the more guesses you get to make... thus the better your chances of winning.

So it depends on your hardware, but honestly, unless you wanna put work in, and drop hardware on the problem, then, the answer is... not much. Look into pooled mining and/or GPUs if its what you really want to do.

Probably almost nothing.

Problem has benn sloved ,thanks 

Oh ,I see .Thanks !

A real answer would be:

In a day, you would on average not make any. However the way it works is you spend the time "mining" and if you "find" a block, you get 50BTC.

That's it. You might not find one for days, weeks even, or you might find one in 2days.

Pools make it so blocks are "found" faster, but you only get a fraction of that 50BTC.