If you want to cultivate your writing ability, the most important thing is to be able to keep reading. Reading can not only improve the child's expressive ability, but also make him more eager to talk after thinking more, so he will want to record his thoughts through words.
Writing slowly is a pleasure for children, who naturally have the motivation to do something, so parents don't need to worry about it. It is a pity that many parents are eager to buy a lot of composition books for their children, and not letting them read extracurricular books will make them hate writing even more.