What are the ancient poems in the first grade of primary school?

What is the ancient poem about crooked neck lying on the table?

Zhang Xiaolin, learn to write. Tilt (w ā i) your neck (bi) and lie on the table (p ā) (Zhu Bu). It's not the posture (Z: and) and posture (Shi: and) of writing, but it will make you nearsighted after a long time (Shi: and). Writing body (sh ē n) should sit up straight, eyes should be one foot (ch ǐ) away from the book (l í), chest (xi is not n) should punch (qu á n) away from the desk (l í), and hands should be one inch (cú n) away from the pen tip (ji ā n).

Hope to adopt! Thank you~