The subject pronoun in the sentence is "they."
<span>The following best describes a vocabulary system called Word Forms:
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B. Learn how a root word changes when used as a noun, verb, adjective, or adverb to learn multiple related words at the same time.
Irascible, irascible means to be easily angered.
It is a simple sentence because it has one subject and one predicate.
B. He wants to make social connections to help advance his career.
