$跟谁学(GSX)$ Shannon Shen -- Chief Financial Officer

Hello, Greg, I'm going to take your second question. So, about the sales and marketing expense per enrollment decreased in this quarter. So, firstly, let's recap what happened in the first quarter in 2020. So, in the first quarter, as we mentioned on our Q1 earnings call, majority of the enrollments are coming from the first-time users.