1. Simple Sentence
A simple sentence, also called an independent clause, contains a subject and a verb, and it expresses a complete thought.

2. A: Some students like to study in the mornings.
B: Juan and Arturo play football every afternoon.
C: Alicia goes to the library and studies every day.
D: Tom, Dick, Harry, and Fred visited us.
E: They swam in the ocean, relaxed on the beach, and ate our food.

3. Compound Sentence
A compound sentence contains two independent clauses joined by coordinators. -Coordinating Conjunctions: for, and, nor, but, or, yet, so. (FANBOYS.) -Correlative Conjunctions: Not only…but also, neither…nor, either…or, both…and etc. -Conjunctive Adverbs: Therefore, however, etc. -Semi-colon (;), (:)

4. A: Eleanor tried a new recipe today; however, she forgot to add the baking soda. (Conjunctive Adv.) B: Not only the Algebra professor gave him a bad grade, but also the Chemistry Professor did so. (Correlative Conjunction) C: Michael played football, for Maria went shopping. (Coma + Coordinative Conjunction ) D: I would like to do some exercise everyday, but I have no time. E: The whistle blew; the parade began. (Semicolon) F: Neither did he listen, nor did he improve. (Correlative Conjunction)

5. Complex Sentence
A complex sentence has an independent clause joined by one or more dependent clauses. A complex sentence always has a subordinator such as because, since, after, although, or when or a relative pronoun such as that, who, or which etc.

6. A: When he handed in his homework, he forgot to give the teacher the last page. B: The teacher returned the homework after she noticed the error. C: The students are studying because they have a test tomorrow. D: After they finished studying, Juan and Maria went to the movies. E: Juan and Maria went to the movies after they finished studying.

7. Complex Sentences / Adjective Clauses
Finally, sentences containing adjective clauses (or dependent clauses) are also complex because they contain an independent clause and a dependent clause.  The subjects, verbs, and subordinators are marked the same as in the previous sentences, and in these sentences, the independent clauses are also underlined. 

8. A: The woman whom my mom talked to sells cosmetics
A: The woman whom my mom talked to sells cosmetics. B: The book that Jonathan read is on the shelf. C: The house which Abraham Lincoln was born in is still standing. D: The town where I grew up is in the United States. E: He raises his hands in order that the bus might stop.

9. Test your understanding
1: The teacher walked into the classroom, greeted the students, and took attendance.
Simple/Compound/Complex
2: Juan played football while Juanita went shopping.
3: Juan played football, yet Juanita went shopping.
4: Although Mexico has the better football team, it lost.
5: The island was filled with many trails winding through the thick underbrush, a small lake, and dangerous wild pigs.
6: Naoki passed the test because he studied hard and understood the material.

10. 8: Until she was 19 months of age, her sight and hearing were normal.
7: Helen Keller was born in Tuscumbia, Alabama, in 1880 and died in 1968.
Simple/Compound/Complex
8: Until she was 19 months of age, her sight and hearing were normal.
9: At the age of 19 months, a severe illness left her deaf and blind.
10: When she was seven, she began her education in reading and writing with Anne Sullivan of the Perkins Institute for the Blind.
11: Through persistence and stubbornness, Anne breaks through Helen's walls of silence and darkness and teaches her to communicate.

11. 12: Helen Keller learned to read by the Braille system, and she learned to write by using a specially constructed typewriter.
Simple/Compound/Complex
13: Later, she entered Radcliffe College and graduated with honors in 1904.
14: Helen Keller's story needed to be told, so in 1962, a beautiful movie was made about her life.
15: "If there were only joy in the world, we could never learn to be brave and patient." -- Helen Keller.
16: "Life is either a daring adventure, or it is nothing." -- Helen Keller.