How do you say

It usually snows in Beijing in winter, and it lasts about two months.

..in Chinese?

北京的冬天通常会下雪,而且会持续大约两个月。

běi jīng de dōng tiān tōng cháng huì xià xuě , ér qiě huì chí xù dà yuē liǎng gè yuè 。

How do you say "I intend to buy a new car in three months’ time." in Chinese?