How do you say

They intend to fly to Africa in three months.

..in Chinese?

他们打算三个月后坐飞机去非洲旅行。

tā men dǎ suàn sān gè yuè hòu zuò fēi jī qù fēi zhōu lǚ xíng 。

How do you say "We are planning to buy a new car." in Chinese?