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friendly; openhearted; sociable; amiable; good-humored; good-humoured; frank; candid; willing; ready
気さくに話しかけてくれた。
She spoke to me in a friendly way.
あの先生はとても気さくな人だ。
That teacher is a very friendly person.
彼女が気さくな性格なので職場に溶け込めた。
Because she's so sociable, she fit in at work easily.