选修...课程的英文：
take classes in

参考例句：

Students have a free choice of courses in their final year.
学生在最后一学年可以自由选修课程。

I will definitely regret it if I take a class without any of my friend in it.
如果我选修的课程没有朋友去上,我绝对会后悔的

take是什么意思：
v. 拿，取；带；获得；采取；承担；吃；耗费；乘，搭；以为；理解；走；抓住

a catch; a take; a taking
捕获量

take a nap; take a snooze
小睡一下;睡午觉

take service with
在￥帮佣

take a lark with
同￥开玩笑

Will you take a check?
你要再核对一下吗？

classes是什么意思：
n. 班级；阶级；种类
v. 分类；把…分等级
adj. 很好的

It is a step class.
这是踏板操训练班。

The class dismissed.
下课了。

The class teacher sectioned the class for dialogues.
老师把班级分组进行对话练习。

The class teacher dismissed the class on time.
教师按时下课。

A second - class letter is slower than a first - class.
二类信比一类信件慢。