Strength grading of cement
[化] 水泥标号
🧩 词语组成解析
[经] 分级, 归类
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];
cement
[si'ment]
n. 水泥;胶合剂;胶接剂;粘固粉;
vt. 粘牢;巩固;（用水泥、胶等）粘结;在…上抹水泥;
🗣️ 情景例句
You have a good command of English.
你的英语水平很好。
It's a nice day today.
今天天气很好。
Three quarters of the world's books and newspapers are written in English.
3/4的书籍和报纸是用英语写的。