Sentence

Sentence

B. A Sentence is a set of words that is complete in itself, typically containing a subject and predicate, conveying a statement, question, exclamation, or command, and consisting of a main clause and sometimes one or more subordinate clauses.

B1. A simple sentence has only one clause. (e.g. The children were laughing.)
a. A compound sentence has two or more clauses. (e.g. (We stayed behind) and (finished the job))
b. The clauses in a compound sentence are joined by coordinating conjunctions: and, but, or, nor, so, then, yet. (e.g. John shouted and everybody waved.)  
c. A complex sentence has a main clause and one or more adverbial clauses. Adverbial clauses usually come after the main clause. (e.g. Her father died (main clause) when (subordinating conjunction) she was very young (adverbial clause))

B2. Some subordinate clauses can come in front of the main clause. (e.g. Although (subordinating conjunction) some snakes are dangerous (adverbial clause) most of them are harmless (main clause))
a. A sentence can contain both subordinate and coordinate clauses. (e.g. Although (subordinating conjunction) she has always lived in France (adverbial clause) she speaks fluent English (main clause) because (subordinating conjunction) her mother was American (adverbial clause) and (coordinating conjunction) her father was Nigerian (adverbial clause))

Sentence Type

B3. Four Sentence TypesDeclarative, Imperative, Exclamatory, and Interrogative Sentences
a. Declarative sentence makes a statement to relay information or ideas, and consists of the subject + verb with the end period (.). (e.g. The class starts from this Friday.)
b. Imperative sentence describes form of a verb that is usually for giving order, desire, or wish. (e.g. Come here!)
c. Exclamatory sentence makes a statement, and conveys excitement or emotion with an exclamation mark (!) at the end. (e.g. Oh! We can’t wait anymore!)
d. Interrogative means a word used in questions, such as how or what. The Interrogative sentence is a type of sentence that asks a question and always ends in a question mark (?). (What’s your name?)

more about the English Structure