Я скрепил отчёт скрепкой, а моя коллега — степлером, потому что страниц было много.

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Breakdown of Я скрепил отчёт скрепкой, а моя коллега — степлером, потому что страниц было много.

• мой: my
• много: many
• быть: to be

Questions & Answers about Я скрепил отчёт скрепкой, а моя коллега — степлером, потому что страниц было много.

Why is the verb скрепил used here, and not скреплял?

Скрепил is the perfective past form, so it presents the action as completed: I fastened the report together.

A native English speaker can think of it as focusing on the result: the report ended up fastened.

By contrast, скреплял is imperfective and would usually suggest:

• an ongoing process,
• a repeated action,
• or background information.

So in this sentence, Я скрепил отчёт... means I fastened the report together as a completed act, which fits the context well.

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Why are скрепкой and степлером in different forms?

They are both in the instrumental case, because they express the tool used to perform the action.

Here:

• скрепка → скрепкой
• степлер → степлером

In Russian, the instrumental case is often used for with / by means of when talking about an instrument:

• писать ручкой = to write with a pen
• резать ножом = to cut with a knife
• скрепить скрепкой = to fasten with a paper clip
• скрепить степлером = to fasten with a stapler

So even though English uses with, Russian often just uses the noun in the instrumental case without a preposition.

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