Can you please explain the separated and joined words in the Quran?

 Question
Can you please explain the separated and joined words in the Quran ?

Answer
There are some combinations of words that are written joined together as if they are one word in some places in the Qur'an or in all places in the Qur'an, or they are written separately.  These are well documented and the memorizer of the Qur'an must know where these places are so he/she knows how to stop properly on these words.  An example is found in  word  and the word , sometimes they are written joined: and other places they are written separately, as seen in red in the following aayah:

You can find the lessons on these words here on the abouttajweed site at the following link:
http://www.abouttajweed.com/al-maqtoo3-and-al-mawsool/index.php
http://www.abouttajweed.com/al-maqtoo3-and-al-mawsool/index.php