В английском языке обстоятельства времени, предшествующие сказуемому, как правило, обособляются запятыми.

Lynne Truss "Eats, Shoot & Leaves"

I was taught to put the commas in a series of object thus:
A, B, and C. However the Washington Post's style is
A, B and C.

Similarly, "data" was considered collective singular when I was taught English. Now it's considered the plural of datum, a word rarely encounterred except by people who want to show off that they know the word :-)

"The problem with commas is difficult and complex. They are mandatory some
times, but rarely. The best rule was to put a comma where you should stop
to breathe when reading the text aloud, so that you keep the sentence
understandable. There are other rules. Mostly, you put a comma where you
feel like it. Some have a better instinct than others. There is a
psychological disease called "comma-craziness". Some people takes an
enormous amount of time pondering whether and where they should put
commas. Some put them almost everywhere. Others write none. There have
been sentences written that have different meaning depending on whether a
comma is placed here or there. This is fun."

[6] Re: а что, поменялись правила расстановки запятых в английском [new]
oleg-ch сегодня, 12:37 Ответить | Ответить с цитированием
Английский вариант "казнить нельзя помиловать":

A panda walks into a café. He orders a sandwich, eats it, then draws a gun and proceeds to fire it at the other patrons.

'Why?' asks the confused, surviving waiter amidst the carnage, as the panda makes towards the exit. The panda produces a badly punctuated wildlife manual and tosses it over his shoulder.

'Well, I'm a panda', he says, at the door. 'Look it up.'

The waiter turns to the relevant entry in the manual and, sure enough, finds an explanation. 'Panda. Large black-and-white bear-like mammal, native to China. Eats, shoots and leaves.'
(http://en.wikipedia.org/wiki/Eat_shoots_and_leaves)