drop someone a line

phrase

(informal)

to write someone a letter, especially a short informal one:

Just drop me a line when you decide on a date.

I hadn't heard from John in ages so I thought I'd drop him a line.

Could you drop her a line and ask her where she got her tent? I'd love to get one myself.

Drop us a line and we'll put your query to our panel of experts.

If I haven't heard from Amber by next weekend I'll drop her a line.

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