Synonyms are often indistinguishable.

Here is a link that will help you Yee. It shows the Chart for ROOTS: http://www.prefixsuffix.com/rootchart.php?navblks=1011000 You can also look for the Chart for PREFIXES and SUFFIXES

My thinking that SHALLOW is not based upon Latin at all is correct, as is show here: http://www.etymonline.com/index.php?allowed_in_frame=0&search=shallow&searchmode=none If you want to know more about the specific distinctions between words in English, I suggest that you begin a study of Latin Roots, Prefixes, and Suffixes, because about 60 to 70 percent of all English words show Latin influence. Most of the rest show Greek influence [Chaos, Cosmos, Logos etc.] and about 10 percent of English is made up of words from other languages of the world.