U-boats
(U-boat 的复数) n. 潜水艇
🧩 词语组成解析
n. 船艇；船（boat的复数）
🗣️ 情景例句
that I never could have done this book
我不可能完成这本书
To protest against something
抗议
This is a major achievement because, in relative terms, planets are very small and old not emit light.
这是一个重要的成就，因为相对来说，行星很小，而且也不发光。