Semidefinite
[计] 半定的
🗣️ 情景例句
Did she say why she had to leave today?
她说了她为什么今天非走不可吗？
Shh! He'll hear you.
咻，小声点，他会听到的。
He agreed that a train did come into the station at the time on the paper and that it did stop, but only to take on mail, not passengers.
搬运工说，正如纸条所说，确有一趟火车在那个时刻到站，但它只停站装邮件，不载旅客。