'当你背对着我的时候'用英语怎么说?

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不同意 enya橙紫 的答案。

When you are back on to me .

back on to sb.才是背对着某人的意思 ！

when you back on me~
back on sb.背对着某人...

When you back into my time '

when you behind me

when you are back to me，.....

enya橙紫的答案是正解！