Tracer composition
[化] 曳迹剂
🧩 词语组成解析
tracer
['treisə]
n. 追踪者，描图者，（铁笔等）绘图工具;
🗣️ 情景例句
Richard and Marilyn bought it for me for my birthday.
这是Richard和Marilyn送给我的生日礼物。
Time past cannot be called back again.
光阴一去不复返。
The leader of the party was examining the soil near the entrance to the cave when the machine showed that there was gold under the ground.
当这个队的队长正在检查洞口附近的土壤时，那台机器显示出它的下面埋有金子。