every是每一，dog是狗，has是有，day是日子，every dog has his /its day可不是“每条狗都有它的日子”，引申为风水轮流转；凡人皆有得意日；人人皆有得意时；人皆有出头日；人皆有得意时；时来运转。

【例句】
Don’t lose your hope, as the saying goes,every dog has his day.
不要灰心，俗话说，凡人皆有得意时。

Just take it as a process of preparation and accumulation and believe every dog has his day.
就把它当作是个积累和准备的过程，并坚信人人都有出头之日。