quavery       
adjective uk/ˈkweɪ.vər.i/ us/ˈkweɪ.vɚ.i/ (also quavering, uk/-ɪŋ/ us)
 (声音)颤抖的
If your voice is quavery, it shakes slightly, usually because you are nervous, frightened, sad, etc.
  "You can't let them in here," he said in a quavery voice. “你不能让他们进来“,他用颤抖的声音说。 
 See: quaver
 - More examples
 - Margaret's voice was still quavery.
 - "What do you want?" she asked, furious with herself for producing such a high, quavery sound.
 - the quavery indecision of her voice
 - Curtis confides in a quavering voice that he's been feeling sad and lonely as one of the few college students living in a violent housing project.