他经常背疼He often _ _ _ _ _ head.=He often _ _ _.=His head often _.

同学,很高兴回答你的问题
首先纠正一下,汉语意思应该是 他经常头疼.
正确答案如下：
He often has a pain on his head.（注意在头上,后背上比较硬的部位用on,在脸上,肚子上比较软的部位用in）
= He often has a headache.
= His head often aches.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
不明白请继续追问,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^