To be competent in his field, he must develop a working knowledge of this aspect.
為了使自己能勝任所從事工作，必須加深這方面知識。
Most adults do not feel competent to deal with a medical emergency involving a child.
大部分成年人不懂得如何對兒童實施急救。
He was a loyal, distinguished and very competent civil servant.
他是一位敬業、優秀而且非常稱職的公務員。