ではありません

1. Origins, structure, and basic meaning

• Structure: Add ではありません after a noun or na-adjective stem for a polite negative.
  • 休みではありません, 静かではありません
• Basic usage: It states that the subject does not have the stated identity, category, or condition.
  • この建物は病院ではありません。 means that this building is not a hospital.

2. Common pitfalls and similar expressions

• Negative i-adjectives and verbs
  • I-adjectives use forms such as 高くありません, and verbs use forms such as 行きません. Do not attach ではありません unchanged to every predicate.
• Not a denial of existence
  • 私の傘ではありません means it is not my umbrella, not that no umbrella exists. Express absence with a form such as 傘がありません.
• Conversational and past forms
  • じゃありません is a conversational form of ではありません.
  • The past negative is ではありませんでした.