Certificate of security
[经] 保证单
🧩 词语组成解析
certificate
[sɚ'tɪfɪkət]
n. 证明书;文凭，结业证书;
vt. 发给证明书;用证书证明（或认可）;
cert 搞清 + ifi=fy表动词 + cate表名词 → certify搞清楚=证明+ cate表名词 → 证件
of
[əv]
prep. 关于;属于…的;由…制成;
aux. 助动词 [非标准用语、方言] =have [主用于虚拟语气];
🗣️ 情景例句
You do. You do. There's a book here.
当然 ，当然。书要出版。
Nothing so bad, as not to be good for something.
塞翁失马，安知非福。
You must get up and get ready for school. If you don't go soon,you'll be late.
你得起床准备上学了。你如果不赶紧去，就该迟到了。