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| Subject | English | Russian |
| gen. | on a prepaid basis | на условиях предоплаты (Sounds less professional than "on an advance-payment basis' or 'on a basis of advance payment' (or 'payment in advance" )  wordreference.com Denis Lebedev) |
| avia. | pre invoiced on a weekly basis and Prepaid before the flights | предварительно выставляя счёт в еженедельном режиме и предоплата осуществляется до рейса (Your_Angel) |