He assisted me in doing my work.

He was very helpful in resolving the issue as our mediator.

She is learning how to use prepositions in Chinese.

In phonetics, a medial refers to a sound that is positioned between vowels in a word.

Kansuke is my best friend.

Shinsuke is my best friend.

Kosuke is my best friend.

Shinnosuke is my best friend.

Yusuke is my best friend.

Kosuke is my best friend.