Open your mouth slightly first, don't open your mouth too wide, and the upper and lower teeth will naturally close.
Second, the tongue end is raised, close to the gums, but not stuck.
Third, the air flows out from the narrow gap between the tip of the tongue and the gums. When the air flows out, it is pronounced with hiss and vocal cord vibration.
4. The [z] in the English phonetic alphabet is a voiced consonant with a soft z, and the words pronounced as [z] include zoo Zoo, zebra zebra, enthusiastic Hot New, zero Zero, busy, Busy business, easy Simple, excuse me, use and advise. Send an s and the vocal cords vibrate at the same time.