This is the 5228th most frequent Chinese word.
上高中
Attend high school.
In this sentence, '上高中' means 'to attend high school', indicating the act of beginning high school education.
我哥哥今年秋天要上高中。
My older brother will attend high school this autumn.
Here, '上高中' refers to the period of attending high school, emphasizing the experience during education.
上高中后,我认识了很多新朋友。
After attending high school, I made many new friends.
In this context, '上高中' designates the duration when she was in high school, highlighting the activities she engaged in during that time.