Usage - Pronoun-Antecedent Agreement. A pronoun is a word used to stand for (or take the place of) a noun. A word can refer to an earlier noun or pronoun in the sentence. Example:
A subatomic particle is a unit of matter or energy that's the fundamental makeup of all matter. According to modern atomic theory, an atom has a nucleus, which is its center, or core. The nucleus contains subatomic particles: protons and neutrons. Protons are positively-charged particles. Neutrons are neutral particles.
The nucleus of an atom has a positive charge. The protons in the nucleus of an atom are charged oppositely from the electrons in the cloud around them. By convention, their châ¦arge is defined as positive while the charge on the electrons is defined as negative.