Definition: used to say what someone is really like Level: C2
她本质上是个孩子。
She is a child ___at ___heart.
他外表强悍，但内心善良。
He seems tough, but he is kind ___at ___heart.
尽管他成功了，但本质上依然谦逊。
Despite his success, he remains humble ___at ___heart.
