Asians tend to add an extra 'uh' sound at the end of some of their words. That's why Siri hears 'sud' and 'soos'. But I hear your 'th' :) You have a th + uh in there. ;) Good job, it's a tricky sound for asians to learn. If it helps, think of 'soothe' as a blue word- has an uuuuu sound. If you associate all words that have this uuuu sound with color blue, this will help you remember pronunciation. Likewise, the word 'bathe' is a gray word similar to 'rain' and 'day'. English words are spelled all different kinds of ways so attaching a color to same sounding words can sometimes help with pronunciation.