trace
/treɪs/
a just detectable amount
中文释义：微量；痕迹
Scientists found traces of lead in the drinking water.
科学家在饮用水中发现了微量的铅。
There was no trace of the missing hiker after the storm.
暴风雨后，失踪的徒步者毫无踪迹。
/treɪs/
a just detectable amount
中文释义：微量；痕迹
Scientists found traces of lead in the drinking water.
科学家在饮用水中发现了微量的铅。
There was no trace of the missing hiker after the storm.
暴风雨后，失踪的徒步者毫无踪迹。