🧩 词语组成解析
trace
[tres]
vt. 跟踪，追踪;追溯，探索;探索;查找;
vi. 沿着一小径或道路前进;可以追溯的;
n. 痕迹，踪迹;微量，极少量;[植]（脉）迹;痕迹;
trace(draw)→回溯
🗣️ 情景例句
Before a long trip I always give my car a safety check.
远行之前，我总是会对车子进行安全检查。
It's been a long time.
好久不见了。
What was the population of the world in 1950?
1950年世界人口是多少？