1. Simple sentences

• A simple sentence contains a subject and verb.
• It expresses a single complete thought.
• A simple sentence is a single independent clause.
   

Sample simple sentences:

• The cat crept through the dark house.
• The wary mouse watched from underneath an upturned cereal box.
• The predatory cat stopped and surveyed his surroundings.

2. Compound sentences

• A compound sentence contains two independent clauses.
• Coordinating conjunctions (for, and, nor, but, or, and yet, so) join these independent clauses. (Hint: The conjunctions spell FANBOYS.)
• The conjunction used can impact the meaning of the sentence.
   

Sample compound sentences:

• The cat was unsuccessful in his attempt to catch the mouse, and the mouse was equally as unlucky in his attempt to get the cheese.  (Use the semicolon instead of the comma+and: The cat .. mouse, and; the mouse...)
• The dog had watched all of this, but he had refused to become involved. (Equal: The dog .. this, but; however, he...)
• The mouse could wait until dark, or he could risk a daylight raid on the pantry.

The usage of semicolons: (Reference: https://www.grammarly.com/blog/semicolon/)

• Semicolons Connect Related Independent Clauses.
  • I ordered a cheeseburger for lunch; life’s too short for counting calories.
• Delete the Conjunction(and, but, or) When You Use a Semicolon.
  • I saw a magnificent albatross, and it was eating a mouse.
  • I saw a magnificent albatross; it was eating a mouse.
• Use Semicolons in a Serial List.
  • I need the weather statistics for the following cities: London, England; London, Ontario; Paris, France; Paris, Ontario; Perth, Scotland; Perth, Ontario.
• Use With Conjunctive Adverbs (also, moreover, however, otherwise, therefore, then, finally...)
  • The students had been advised against walking alone at night; however, Cathy decided walking wasn’t dangerous if it was early in the evening.

3. Complex sentences

• A complex sentence is an independent clause joined by one or more dependent clauses.
• A subordinating conjunction begins the dependent clauses.
  • Common subordinating conjunctions: After, Although, As, As long as, As much as, At least, Because, Before, Even though, Even if, How, However, In order to, Now that, Since, So that, Soon, Though, When, Whenever, Whereas, Wherever, Until
• A dependent clause that begins a sentence must be followed by a comma.
• A dependent clause has a subject and a verb, but it does not make sense on its own.

Sample complex sentences:

• After he gave it some thought, the mouse decided to wait until later for his trek.
• The cat fell asleep on the warm kitchen because he was deprived of sleep the night before.
• When the mouse heard the soft snoring of his sleeping nemesis, he scurried to the pantry and grabbed enough food for a week.

4. Compound-complex sentences

• A compound-complex sentence is a sentence that has at least two independent clauses and at least one dependent clause.
• The same subordinating conjunctions are used to introduce the dependent clauses.
• The same coordinating conjunctions (FANBOYS) are used for joining the independent clauses.

Sample compound-complex sentences:

• After the two adversaries had spent years playing this “cat and mouse” game, they were joined by their children, and the fun continued.
• Even though it seems the two were bent on the other’s destruction, the cat and mouse were rather fond of one another, and neither wanted the other’s defeat.