? BC? Is it? The first year of AD? Before. We are now in 2020, right? After AD? . Of course, under normal circumstances, we don't say? After AD? These three words, officially, are simply said? In 2020? . As for what period, you can understand it as before Jesus was born. BC? The year when Jesus was born? The first year of AD? It is based on the year when Jesus was born.

According to the date of China, the first year of A.D. is the first year of Emperor Yuan of Han Ping, 0 1.

So we can also say. BC? It was the year before Emperor Han Ping ascended the throne. What was the year when Emperor Han Ping ascended the throne? The first year of AD? .

Actually, it's very simple to understand this dating method. First, draw a straight line at will, on paper, on the ground or on the wall. Straight line direction from left to right.

Then draw a point in the middle (anywhere in the middle).

We call the middle point. The first year of AD? This year is the birth year of Jesus.

What is the left part of this point? BC? What is the correct part? After AD? The vertex on the right is this time of the month.

To put it bluntly, AD? Is a benchmark, we use this as a benchmark to calculate the year and month, otherwise what should we call the year and month? After all, in 2020 this year, there are still 2020 nodes from the first year of AD, so this year is 2020. If the node changes, then this year's statement will inevitably change.

But what should be noted? BC? What year is it? Walk backwards? Right, first? 2 BC? And then the next year? Bc 1? The bigger the number, the farther away from modern times.

As for why take the birth date of Jesus as an example? First year? It can only be said that we have chosen a common calculation method. Whether it is Jesus' birthday or Qin Shihuang's birthday this year, there is no difference in essence, just a basic point.