The United States has five years in elementary school, three years in junior high school and four years in senior high school.

But don't say what grade is in primary school, junior high school and high school, just what grade.

Primary school 1~5 grade, junior high school 6~8 grade, senior high school 9~ 12 grade.

Undergraduate majors are generally four years, and medical and legal majors are five or six years.

But some people can't finish it in ten years. Unlike domestic colleges and universities, paying money can almost upgrade and graduate.

There are also schools offering undergraduate and master's degrees, most of which are five years.

I'm not a child anymore. American college students decide how many classes to take and what classes to take (some decisions can be made by themselves in American high schools). You can choose 3~5 courses, with one semester 12~ 15 credits (less than 12 credits, not full-time students); Can also be accelerated, one semester 19 credits (generally not allowed to exceed 19 credits); You can also work-study programs or mix schools slowly, learning one lesson each semester, and no one cares.

However, international students must be full-time students, that is, more than 0/2 credits per semester.

Practice class (or study work) is a junior or advanced class. In the same way, it's up to you.