Placoderm
n. [古生]盾皮鱼
🗣️ 情景例句
I enjoy writing.
我喜欢写作。
It is dogged (that) does it.
天下无难事，只怕有心人。
The second marks the arrival of transverse vibrations which travel more slowly and arrive several minutes after the first.
然后记录下的是横向波的到达，横向波比纵向波传播得慢，在纵向波到达几分钟后才能到达。