Not always put -s to make a plural word. That's what we call irregular nouns. Can you give any other examples? Comment below!
Por um escritor misterioso
Descrição
Grammar, spelling, and other such learning experiences – The Geeky Gaeilgeoir
Use irregular plural nouns correctly
Learn English Through Stories – Why People Abhor Bacteria - Prospero English
Simple Past Vs. Past Progressive – Ellii Blog
Semicolon Rules and Practice Sheets (free) - Homeschool Den
American English at State - A few and a little are commonly used quantifiers that express a nonspecific amount of something. With plural count nouns, use a few. Use a little with
How to build a Lemmatizer. And why, by Tiago Duque, Analytics Vidhya
Advice Archives - CIEP blog
What's New – Page 3 – ENGLISH – Your Way!
Spanish Grammar in Context - A reference grammar with video examples from the Spanish in Texas collection
Easy Ways to Teach Grammar
ELT Concourse language analysis course Unit 3: content words
de
por adulto (o preço varia de acordo com o tamanho do grupo)