～きり— Only / And Never Since

• 二人きりで話したい。

  Futari kiri de hanashitai.

  I want to talk just the two of us.

  Noun 二人 + きり = 'only the two', limiting sense

• 彼は出かけたきり、帰ってこない。

  Kare wa dekaketa kiri, kaette konai.

  He went out and hasn't come back since.

  出かけた (past) + きり = 'since going out', with no change after

• 祖母とは十年前に会ったきりだ。

  Sobo to wa juunen mae ni atta kiri da.

  The last time I saw my grandmother was ten years ago.

  会った (past) + きりだ = met once and never again since

• ・Two uses: 'only/just' (like だけ) and 'since X, no change' after た-form.
• ・The 'no change' sense implies an expected next step never happened.
• ・っきり is a common emphatic spoken variant.

Commonly confused with

The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ～きり is tested against.

• ～一方だ — Heading Ever Further In One Direction
• ～がちだ — Prone To It
• ～からいうと／からいえば — Speaking In Terms Of
• ～からして — Even Just From
• ～かわりに — Instead Of / In Exchange
• だらけ — Covered All Over
• っけ — What Was It Again?
• ～っぱなし — Left As It Is