We usually deal on a 20% trade discount basis with an additional quantity discount for orders over 1000 units.
我们通常给予20%的商业折扣,外加订货1000件以上的数量折扣。
About once a month. Not too often, because neither of us has much time. We both have too much work to do.
大约每月一次。不太经常写信,因为我俩的时间都很紧。我们都有做不完的事。