A complete thought expressed in a single clause that can stand alone as a grammatical sentence. It contains a subject and predicate. Sentences can be simple, compound or complex.
One traditional scheme for classifying sentences according to their structure is by number of independent clauses without dependent clauses. A simple sentence has a single independent clause and no dependent clauses; a compound sentence has multiple independent clauses and no dependent clauses; and a complex sentence has an independent clause and at least one dependent clause.
An independent clause can have more than one subject, but only if they are sharing the same verb. These subjects are joined using coordinate or correlative conjunctions.
Example: The Taj Mahal is magnificent. (The adjective magnificent describes the subject, Taj Mahal). Voters elected her as a member of Parliament. (The noun phrase member of parliament describes the subject, her). Smoking cigarettes is harmful to health. (The noun phrase cigarettes describes the subject, health).
A simple sentence can contain multiple verbs or even no verbs. This is called a compound verb or a compound predicate. Compound verbs or compound predicates occur when a single subject performs more than one simple predicate, but does not include a compound object. Examples: She has a ring and lives in Dubai. (She and Ashok are subjects; she has a ring and lives in Dubai are predicates.) She is tired after working all day. (She is a doctor and she works long hours.)