I must go now. Because my sister is waiting for me at the school gate.
祝你学习进步,更上一层楼!(*^__^*)
有不会的可以再问我:)
I must go now. Cuz my (older) sister is waiting for me at the school gate.
(cuz是because...)
I must go. My sister is waiting for me at the gate of school.
I must go.My sister is waiting for me by the school gate.
I must go now. My sister is the school gate waiting for me
I must leave/go now.My sister is waiting for me at the school gate