Here are a few more pronunciation rules. It is important to keep this in mind:
 

All the rules you've already learned plus these new ones are there to make the flow of Korean easier. And once you start getting the hang of it, these rules/simplifications will start to come to you naturally.
 

Listen to this example:
 

Notice how the final Pat'chim consonant sounds like a "t" even though it is written "s"? Why would you change the pronunciation? The reason is related to the Pat'chim swallowing rule you learned in the lesson Complex Blocks. When the final consonant is a Pat'chim you move your mouth to make the sound of the Pat'chim but you never make the final breath of air that articulates the sound.

Try this. Without making any sound, make your mouth in the shape to make a "t" sound, basically just make your tongue touch the top of your mouth. Easy right? Now, make your mouth in the shape to make an "s" sound without actually making any noise. It's more work right? You need to round your lips and tense up your face.

Now look to this example:
 

Notice how the "t" in "mada" flows into the following "d". But the actual spelling is "mashisda" with an "s". But if you try saying that you will notice that the "s" doesn't flow into the "d" as smoothly. In order to make the pronunciation of