Types of Sentences

First, you will find important definitions:
Definitions
Sentence: a group of words that contains at least one subject, at least one verb and expresses a complete idea. 
Clause: a group of words that contains one subject and one verb. 

• When a clause expresses a complete idea, it is called independent clause.  
• She needs to debug the application.
• When a clause does not express a complete idea, it is called dependent clause. Dependent clauses can be adjective clauses, noun clauses, or adverbial clauses.
• If she debugs it.

Phrase: two or more words that lack subject, verb, or both.
Types of Sentences
There are four types of sentences:

• Simple Sentence: it is an independent clause (one subject + one verb + complete idea)
• Compound Sentence: it is two independent clauses joined by a coordinating conjunction or by a conjunctive adverb. 
• Complex Sentence: It is one independent clause joined to a dependent clauses by a subordinating conjunction, relative pronoun, or other forms. 
• Compound-Complex Sentence: two independent clauses joined to a dependent clause. 

Types of Dependent Clauses

As mentioned above, there are three types of dependent clauses:

• Adjective Clauses: modifies a noun
• Adverb Clauses: works as an adverb, modifying the verb
• Noun Clauses: works as subject or object