Closed under union
[计] 对\或\运算封闭
🧩 词语组成解析
closed
[klozd]
adj. 关闭着的，封闭着的;密闭着的，保密的;<美>准备好了的，定了契约的;
v. “close”的过去式和过去分词;
clos=close关闭+ed已...的→关闭了的
under
['ʌndɚ]
prep. 在…下面，在表面之下;在…的假定表面或掩饰下;少于，小于;在…情况下;
adv. 在下面;少于;在水下;在昏迷中;
adj. 较低的，下面的;
🗣️ 情景例句
When you arrive, be sure to register with you consulate.
你到达时，记得去领事馆登记。
Don't try judge young people by their appearance.
不要从外表去判断年轻人。
These satellites go round the earth and help us to learn more about the earth, the weather and other things.
这些卫星绕着地球转，帮助我们更好地了解地球、天气和其他情况。