在询问“你们在哪个学校留学英文”时，可以使用以下几种表达方式：
Where are you studying？
Which school are you studying at？
Which university are you studying at？
Where is your new school？
Which school are you attending/in/from？
这些表达方式都可以用来询问对方目前所在的学习地点或学校。根据具体的语境和需要，可以选择最合适的问法。例如，如果是在口语中，可能会更倾向于使用“Where are you studying？”或“Which school are you studying at？”这样的表达，因为它们更为自然和常用。而在书面语或正式场合，可能会选择更为正式的“Which university are you studying at？”或“Which school are you attending/in/from？”来表达。