Samsung Galaxy S4: How to Fix Missing Microphone Button on Samsung Keyboard

In the stock Samsung keyboard, there are some keys that have several functions, for instance a key in the left side of Space bar(it's usually displayed with a Settings/Cog wheel icon), when you long tap this key, you will see some options available, such as Keyboard settings, Smiley, Clipboard, Microphone, etc. Those hidden button sometimes make some users who want to use one of them have