Year 1 are learning to read a story

We are also learning about using numbers in a sentences in Chinese. There are two ways to say “two” in Mandarin Chinese: 二 (èr) or 两 (liǎng). These characters cannot be used interchangeably so it’s important to know when it is appropriate to use which form.

https://www.thoughtco.com/two-mandarin-twos-2279412