Riprapping
抛石
🗣️ 情景例句
Your first great-grandchild.
你的第一个曾孙。
I locked all the doors.
我锁好了所有的门。
for fear the agents of other firms should be able to trace the kind of research they are likely to be undertaking.
他们生怕别的公司的情报人员据此摸到他们可能要从事的某项科研项目。