YOU SAID:

my friend will fail his exams

INTO JAPANESE

私の友人は彼の試験に失敗します。

BACK INTO ENGLISH

My friend fails his test.

INTO JAPANESE

私の友人は、彼のテストを失敗しました。

BACK INTO ENGLISH

A friend of mine failed his test.

INTO JAPANESE

私の友人は、彼のテストを失敗しました。

BACK INTO ENGLISH

A friend of mine failed his test.