Then each rode in three separatetrials, wearing headphones tuned to their preferred volume.
三个试验同时分开进行，志愿者们都佩戴耳机，并调到他们舒服的音量。
2
Trials on using supplements to prevent infections have given mixed results, so the researchers pooled data on 11,321 people from 25 separatetrials to try to get a definitive answer.
Trials son using supplements to prevent infections have given mixed results, so the researchers pooled data on 11,321 people from 25 separatetrials to try to get a definitive answer.