A paragraph in writing is what you send someone when you want to submit a complaint. You want to make sure these are in writing, though, otherwise you don't have proof of your complaint. Also, don't make it longer than a paragraph, because that's too long and nobody cares about how you think the shop staff mistreated your dog Fluffy.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
Koichi complained incessantly about the Tofugu employee's JLPT results.
I think Tofugu is, without a doubt, the best of the online Japanese learning tools.
It’s funny that the Japanese word for complaint is pronounced like the English word monk.