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.
1 Subatomic particles are particles that are smaller than the atom. 2  Protons, neutrons, and electrons are the three main subatomic particles found in an atom.  Protons have a positive (+) charge. An easy way to remember this is to remember that both proton and positive start with the letter P..