Analysis: the sentence tense is the simple present tense, the subject is the pen, and the predicate verb is? However, the object is a pencil box, and the main components of the sentence are complete. Because it is in the box, the preposition in is used. So on the whole, this sentence is correct.

Keywords: pencil

Usage of pencil:

Pencil is a countable noun, which basically means "pencil", especially a pencil with a wooden core. The preposition with or in is used to mean "draw or write with a pencil".

Pencil extension can stand for "pen", which is used in optics and can also be used as a solution of "light cone".

Examples of using pencils as nouns:

He wiped away the pencil marks. He erased the pencil marks.