じっくり
1. (slowly and) carefully, without haste, thoroughly, deliberately, closely, meticulously
（缓慢而）谨慎地，仔细地，一丝不苟地
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@ ゆっくり
1. slowly, unhurriedly, without haste, leisurely, at one's leisure
2. easily (e.g. in time), well, sufficiently, amply, with time to spare
3. well (e.g. sleep), comfortably
缓慢地，不慌不忙地，不急不躁地，悠闲地，从容地；轻松地(例如在时间上)，很好，足够，充裕，还有时间剩余；舒适地(例如睡觉)