Breakdown of Он посмотрел внутрь коробки.
он
he
посмотреть
to look
коробка
the box
внутрь
inside; inward (direction)
Questions & Answers about Он посмотрел внутрь коробки.
Why is the verb посмотрел and not смотрел?
Because посмотрел is perfective, while смотрел is imperfective.
- посмотрел = he looked / he took a look
- смотрел = he was looking / he looked for some time
In this sentence, the action is seen as one complete act: he looked inside the box. That is why посмотрел is natural.
Compare:
- Он посмотрел внутрь коробки. = He looked inside the box.
- Он смотрел внутрь коробки несколько минут. = He was looking inside the box for several minutes.
What does внутрь mean here?
внутрь means inside, into the inside, or more literally inward.
In this sentence, it shows the direction of the gaze: he looked into the inside of the box.
A useful contrast is:
- внутрь = to the inside / inward
- внутри = inside / on the inside as a location
So:
- Он посмотрел внутрь коробки. = He looked inside the box.
- Что внутри коробки? = What is inside the box?
Why is it коробки and not коробка?