simple past tense and past participle of widthen

present participle of convince

(organic chemistry) The phenolic carboxylic acid (2R,3R,4S)-6-hydroxy-4-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-7-methoxy-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid

simple past tense and past participle of somber