in / into / inside / within

In and inside are the same in many cases. You can say:

  • We are in the house.
  • The clothes are in the closet. or The clothes are inside the closet.

    The word inside implies that the thing is physically enclosed – it is in a container (a box, a vehicle, a building with walls, etc.)

    This means that when talking about location, time, being included, or other situations where you are not physically surrounded, you should use in, not inside:

  • I live in Australia.
  • My birthday is in July.
  • He plays guitar in a band.

    The word into implies movement or transformation:

  • She jumped into the swimming pool.
  • We went into the house.
  • The car crashed into a telephone pole.
  • The caterpillar turned into a butterfly.

    With the verbs put, throw, drop, and fall, you can use either into or in:

  • He put the card into/in his pocket.
  • I threw the paper cup into/in the trash.
  • She lost her balance and fell into/in the river.

    The word within means “inside the limits” – and in this case the limits are nonphysical. They can be limits of time or distance, or an area of understanding:

  • The results will be delivered within fourteen days.
  • Most car accidents occur within five miles of home.

    We also have some expressions using within:

  • within earshot = at a distance where you are able to hear something (such as a conversation)
  • within reason = to the degree that good judgment would allow
  • within reach / within one’s grasp = able to be taken with your hand, or able to be accomplished

    You can also use within to describe a person’s inner feelings (in this case, you can also use “inside”):

  • He tried to hide the anger burning within/inside him.