The idiom "drop a line" means to write a short message or letter to someone. It is often used to refer to sending a quick note or email to someone to let them know you are thinking of them or to update them on something.
For example, if you haven't heard from a friend in a while, you might say "I should drop her a line to see how she's doing." Or if you want to follow up with a colleague after a meeting, you might say "I'll drop him a line to confirm the details."
The phrase can also be used more broadly to refer to any form of communication, not just writing. For example, you might say "I'll drop him a line to give him a call later."
Overall, "drop a line" is a casual and informal way to refer to sending a message or communicating with someone.
• I need to drop a line to my supervisor to inform him of my resignation.
• I decided to drop a line to the editor of the newspaper to express my opinion on the recent article.
• As an established author, I often drop a line to other writers to offer encouragement and advice.
• Could you please drop a line to the customer service department to report the issue?
• I will drop a line to my friend to let her know I will be late.
• I always drop a line to my parents when I travel to keep them updated.