【熊熊讚】評論

The teacher’s six-month practical training at a local middle school proved invaluable to his professional knowledge and teaching skills.這位老師在當地一所中學進行了為期六個月的實踐培訓，這對他的專業知識和教學技能來說是無價的。(A) value名詞+動詞  n. 重要性，益處[S][U]；價值；價格[C][U] · vt. 估價，評價

【咖啡】評論

prove + 形容詞是…例句：The rumor proved true.那謠言結果是真的。The teacher’s six-month practical training at a local middle school proved invaluable to his professional knowledge and teaching skills.這位老師在當地一所中學進行了為期六個月的實踐培訓，這對他的專業知識和教學技能來說是無價的。(引自B1)因此答案為(D)參考資料:https://barshai.org/word-dive/prove/