Scientists are confident in their calculations, putting the comet's last pass through the solar system at 50,000 years ago.

科学家们对他们的计算很有信心，他们认为这颗彗星上一次穿过太阳系是在5万年前。

Okay, this is the last pass.

好的，这是最后一关。

They all laughed except Hermione, who ploughed on, " So, after 'E' it's 'A' for 'Acceptable', and that's the last pass grade, isn't it? "

他们都大笑起来，只有赫敏没笑，她不屈不挠地探讨着这个话题：“那么，‘E’后面是‘A’，代表‘及格’那是最低的及格线，是不是？”