"We are leaving from school" 是一种常见的表达方式。
"Leaving from" 是一个介词短语，意思是 "从...出发"。 "From" 是介词，表示 "从...开始"。 "Leaving" 是动词，表示 "离开"。
例句:
"We are leaving from school" (我们从学校出发)
"We are departing from the office" (我们从办公室出发)
"We are setting off from the train station" (我们从火车站出发)