No, stop is present tense. The past perfect tense is had stopped.
There is no verb in the past perfect tense in that sentence. The past perfect tense of stop is had stopped. Stopped is the past tense.
The past tense of stop is stopped. The present tense of stop is stop.
Had stopped
had toldhad + past participleI had told him before to stop kicking the ball.
The past perfect tense for "stop" is "had stopped."
Existed is the past tense. The past perfect tense is had existed.
The past perfect tense of "stop" in the given sentence would be: "The storm had stopped in the early afternoon."
The past tense is bled, and the past perfect tense is had bled.
The past tense of sit is sat; the past perfect tense is had sat.
The past perfect tense of hope is had hoped.
The past perfect tense is had set.
The past perfect tense is had submitted.