YOU SAID:

I haven't brushed my hair since high school.

INTO JAPANESE

私は高校時代から髪を磨いていません。

BACK INTO ENGLISH

I have not brushed my hair since high school.

INTO JAPANESE

私は高校時代から髪を磨いていない。

BACK INTO ENGLISH

I haven't brushed my hair since high school.

INTO JAPANESE

私は高校時代から髪を磨いていません。

BACK INTO ENGLISH

I have not brushed my hair since high school.

INTO JAPANESE

私は高校時代から髪を磨いていない。