改

改

"改" means "change," "modify," or "revise."

In this sentence, "改めた" (aratemata) is derived from the word "改" (kai), meaning "revise" or "change." The context reveals the usage of "改" to indicate making amendments or improvements.

私は計画を改めた。

I revised the plan.

Here, "改良" (kairyō) is a compound word where "改" (kai) signifies improvement or adjustment, combined with "良" (ryō) for betterment. The overall meaning pertains to enhancing or upgrading something.

古い制度は改良が必要だ。

The old system needs improvement.

In this case, "改正" (kaisei) uses "改" (kai) to connote amendments or corrections. It is combined with "正" (sei), which implies making things right or correcting mistakes.

その法律を改正すべきだ。

That law should be amended.