The clause that modifies the noun
S (plain form) + N
A whole clause can go in front of a noun to describe it, always in the plain form: ミラーさんが 住んでいる 家 (the house Mr. Miller lives in), 京都へ 行く 人 (the people going to Kyoto). The subject inside the clause is marked with が.
Examples
これは 母が 作ったケーキです。
This is the cake my mother made.
眼鏡をかけている 人は 誰ですか。
Who is the person wearing glasses?