Can you put these letters into the pillar-box for me?

你能帮我把这些信投入邮筒吗？

A pillar box for me to post letters stands in a petrol kiosk.

在加油站里有一个供我寄信的邮筒.

A pillar box for me to post letters stands in a petrol kiosk .

在加油站里有一个供我寄信的邮筒。

He stopped at the pillar-box and dropped the letter in.

他在信筒前停了下来，把信投了进去。