Quote Originally Posted by Alex80 View Post
(b) is more universal, can be said in any situation. default word ordering.
We can emphasize any word during speech without reordering of words, just by tone of voice.
But sometimes semi-rule can be used: place important (emphasized) words in first positions.
So, situations exist where (b)-form is good, but I doubt it can be explained easily. Just read/listen natives and get used to common patterns.
Я начал изучать русский в 2012 году и ещё я не понимаю простые вещи!