you are turning off the laptop computer. Have you finished...?

You are turning off the laptop computer.
Have you finished turning off your laptop computer?

Penjelasan:

Rumus Present Perfect Introgative: (jawab)
Have/has + S + V3 + Object

Rumus present continuous positive: (soal)
S + tobe (v1) + ving + Object

Didalam bahasa inggris tidak diperbolehkan menggunakan 2 verb.
Jadi, bukan Have you finished turn off the laptop. << salah.

Supaya tidak terjadi kefatalan itu, gunakan gerund yaitu Turning.

Kamu sedang mematikan komputer, apa kamu sudah selesai?