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前もって, 前以て, まえもって
1. in advance, beforehand, previously, ahead of time
提前,事先,先前,预先
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予約, よやく
1. reservation, appointment, booking, advance order
2. contract, subscription, pledge
3. programming (e.g. a device), setting (e.g. a timer)
预约,预订;订阅
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なければならない, なければなりません, なければいけない
1. have to do, must, should, ought to
必须,应该