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shield; buckler; escutcheon; pretext
騎士は盾で敵の攻撃を防いでいた。
The knight was blocking the enemy's attacks with a shield.
彼は彼女を盾にして逃げようとした。
He tried to escape using her as a shield.
この盾は金属製でとても重たい。
This shield is made of metal and very heavy.