1993年，我们开始培训国际商务自费生。

In 1993, we started to train self -paying students for international business.

居留证有效期限（不超过护照有效期）不超过一年，自费生由交纳学费期限而定。

The visa is valid for less than one calendar year (not to exceed the passport's expiration date). For self-supporting students, the period of validity is determined by the tuition paid.