Which letters are element symbols?

Names and pronunciations: 1 Hydrogen H (clear), 2 Helium He (harmful), 3 Lithium Li (Li), 4 Beryllium Be (Pi), 5 Boron B (Pi), 6 Carbon C (tan), 7 Nitrogen N (light), 8 Oxygen O (foster), 9 Fluorine F (F), 10 Neon Ne (Nai), 11 Sodium Na (Na), 12 Magnesium Mg (M), 13 Aluminum Al (Lv), 14 Silicon Si (return), 15 P (Lin), 16 Sulfur S (stay), 17 Chlorine Cl (green), 18 Calcium Ca (Ya), 19 Potassium K (A), 20 Calcium Ca (Ya), 19 Kassium K (A), 20 Calcium Ca (Ya). S (stay),17 Chlorine Cl (green),18 Argon Ar (sub),19 Potassium K (a),20 Calcium Ca (cover),21 Scandium Sc (resistance),22 Titanium Ti (too),23 Vanadium V (annoyance),24 Chromium Cr (a),25 Manganese Mn (fierce),26 Iron Fe,27 Cobalt Co (ancient),28 Nickel Ni (Nie),29 Copper Cu (the same),30 Zinc Zn (heart),31 Gallium Ga (home),32Ge (germanium),33As (arsenic),34Se (selenium),35Br (bromine),36Krypton Kr (grams)