你到那兒后給我寫封信。
Drop me a line when you get there.
他偶爾給我寫封信。
He sometimes writes to me.
給我們寫封信，能收到你的信總是讓人很高興。
Drop us a line, it's always great to hear from you.
你可以給他打個電話或者給他寫封信。
You can call him or write to him.
我買了這雙鞋，這樣我就可以在星期天給媽媽寫封信了。
I bought this shoes, so I could print a bit of a letter to mother on Sunday.
那位老人要我替他寫封信。
The old man asked me to write a letter for him.