To say "it is in the box" in Engpsh, you can simply say "it is in the box." Here is the sentence in full:

"It is in the box."

This sentence is used to describe the location of an object, indicating that the object is contained inside a box. The word "it" refers to the object, and "the box" is the container in which the object is located.

Here is another example of how you might use this sentence in a context:

Person 1: "Do you know where my keys are?"
Person 2: "Yes, I saw them on the kitchen counter. They are in the box now."

In this conversation, Person 2 is telpng Person 1 that the keys are inside a box and are currently located on the kitchen counter.