A sentence is an arrangement of words that conveys a meaning. A sentence can express a general idea, pose a question or argument, make a request, provide an explanation, classify items into categories, and much more.
The basic parts of a sentence are the subject and the predicate. The subject is the word or phrase that is the center of the sentence; the predicate is the thing about that subject that the sentence is saying. The form (declarative, interrogative, imperative, or exclamative) and meaning of a sentence are separate; for example, the declarative “Can you pass me the salt?” is different from the interrogative “Can’t you do anything right?”
Sentences can be grouped according to their structure: simple, compound, and complex. A compound sentence consists of two or more independent clauses joined by appropriate marks of punctuation, while a complex sentence contains at least one dependent clause. A compound-complex sentence contains two or more independent clauses and at least one subordinating conjunction.
In addition, sentences can be grouped according to their function: statement, question, or command. In a paragraph, sentences should be organized in a coherent manner that supports the controlling idea of the paragraph. To do so, it is helpful to be consistent in point of view, verb tense, and number. For example, using the personal pronoun “you” when referring to yourself in one sentence and then using the impersonal “one” in another undermines the coherence of your paragraph.