Can you provide some simple argument examples to help illustrate the concept of deductive reasoning?

Here are some simple examples of deductive reasoning:

1. All humans are mortal. John is a human. Therefore, John is mortal.

2. If it is raining, then the ground will be wet. The ground is wet. Therefore, it is raining.

3. All squares have four sides. This shape has four sides. Therefore, this shape is a square.

In deductive reasoning, if the premises are true and the logic is valid, the conclusion must also be true.