, Use "is" if the person continues to be during the part/romantic relationship you are referring to, and "was" if they're not in that part/marriage any more. Scientific plausibility: Critics argue that homeopathic ideas, which include Excessive dilution and the "regulation of similars," lack scientific plausibility and contradict recognized concepts https://maps.app.goo.gl/JU7hwR6FT2pvRxCo6