There is a plurality of solutions that conform to the boundary conditions, which is that the system must be bound.

这有许多解决方式,来遵守这个有界条件，那个系统必须是有界的。

麻省理工公开课 - 固态化学导论课程节选

This is a bound system. It is bound.

是一个有界的系统，有界的。

麻省理工公开课 - 固态化学导论课程节选