The woman who / that lives next door is a doctor. となりに住んでいる女性は医者だ。 Where is the cheese that / which was in the fridge? 冷蔵庫にあったチーズはどこ？ このふたつの文の who, which, that は、relative clause（関係詞節）の主語の役割をしています。

The level of grammatical understanding needed rises significantly between LKS2 and UKS2. One area requiring a very strong grammatical understanding in KS2 is relative pronouns and relative clauses.

An essential relative clause provides necessary, defining information about the noun. On the other hand, non‐ essential relative clauses provide additional, non‐necessary information about the noun.

A relative clause can be used to give additional information about a noun. They are introduced by a relative pronoun like 'that', 'which', 'who', 'whose', 'where' and 'when'. For example: I won’t ...

春うらら、いい季節になりましたね。そして日本はゴールデンウィークですから、どこかにお出かけの方も多いことでしょう。"Right now, Japanese people must enjoy days off this week, which is called Golden Week."と、うらやましい気持ちを込めて一言いいたくなるときです。