'' TH'' PUT THE TIP OF THE TONGUE BACK TEETH TOP AND BLOW. THIS SOUND DOES NOT EXIST IN PORTUGUESE.
There are two sounds "th", "th" silent (voiceless) (The vocal cords do not vibrate)'' th "sound (voiced) (The vocal cords vibrate)
"TH" MUDO (VOICELESS 'TH"
The TH sound - looks like O sapo spoken with tongue stuck on the front teeth.