How do you say

Four months later, I took the high-speed train to Beijing with friends.

..in Chinese?

四个月后,我和朋友一起乘坐高铁去北京。

sì gè yuè hòu , wǒ hé péng yǒu yì qǐ chéng zuò gāo tiě qù běi jīng 。

How do you say "It's fine and pleasant to take a walk in Beijing today." in Chinese?