In the same vein, ascenders and descenders should share a similar length.

同一行字母的上下部分也要保持长度一致。

A baseline is the bottom of most letters, where the descender goes under.

大部分的字母都在基线上面，下一行的字母则在基线的下方。

To differentiate between letters like " a" and " d" or " a" and " q" , ascenders and descenders should be sufficiently longer.

为了区分字母“a”、“d”或者“a”、“q”，字母的上半部分或者下半部分要拉得足够长。

After that, it should split into two parts: an orbiter and a descender.

之后，它应该分成两部分：轨道飞行器和下降器。