她报名参加了一门为期三个月的法语课程。

She signed up for a three-month ___course in French.

河流改变了原来的流向，现在朝东流去。

The river altered its ___course and now flows eastward.

我们的第一道菜是蘑菇汤。

Our first ___course was mushroom soup.

他们在砌墙时确保每一层石头都对齐。

They made sure each ___course of stones was perfectly aligned when building the wall.

在大多数情况下，感情的发展应该顺其自然。

In most cases, the development of emotions should follow its natural ___course.