introduction可数吗?

Introduction用法例句

camera has undergone only two minor tweaks since its introduction.

这款相机自推出以来仅进行过两次小的改进。

ions of words have been written about the introduction of the euro.

有关采用欧元的文章数不胜数。

3.I tutored a two-day Introduction to Chairmaking course at the college.

我在那个学院教过为期两天的'椅子制作入门课。

4.A prolonged drought had necessitated the introduction of water rationing.

由于持续干旱，有必要对用水实行配给了。

introduction of student loans

学生贷款的推行