like: How old were you whyou learned to drive? → →
1977
How old were you whyou learned to drive? ☊ 
Cậu bao nhiêu tuổi khi cậu học lái xe? ☊ How old were you whyou learned to drive? ☊ Cậu bao nhiêu tuổi khi cậu học lái xe? ☊