这门课程的招生人数限制在五十名学生。

The enrollment for this course is ___limited to fifty students.

这个折扣仅限前一百名顾客。

This discount is ___limited to the first hundred customers.

这次销售仅限于本周末，所以不要错过。

The sale is ___limited to this weekend, so don't miss out.