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hit it off with (a person); find a kindred spirit in (a person); sympathy; mutual understanding
初対面だが意気投合して長く話した。
Although we just met, we hit it off and talked for a long time.
趣味が同じで意気投合した仲間ができた。
I made friends who share the same hobbies and we really hit it off.
二人は意気投合し共に事業を始めた。
The two hit it off and started a business together.