A sentence can offer a moment of quiet, it can crackle with energy or it can just lie there, listless and uninteresting.
What makes the difference? The verb.
Verbs kick-start sentences: Without them, words would simply cluster together in suspended animation. We often call them action words, but verbs also can carry sentiments (love, fear, lust, disgust), hint at cognition (realize, know, recognize), bend ideas together (falsify, prove, hypothesize), assert possession (own, have) and conjure existence itself (is, are).