Be certain of
公共 Public確信
?? 詞語組成解析
be
[bi]
v. 是;有，存在;做，成為;發生;
aux. 用來表示某人或某物即主語本身，用來表示某人或某物屬于某一群體或有某種性質;
certain
['s?:t?n]
adj. 某一;必然的;已確定的;
pron. [動詞用復數]某些;
of
[?v]
prep. 關于;屬于…的;由…制成;
aux. 助動詞 [非標準用語、方言] =have [主用于虛擬語氣];
??? 情景例句
Turn the key before you pump the pedal, or you'll flood the engine.
加水之前轉動鑰匙，要不發動機就給澆滅了。
I beg your pardon.Is this seat taken?
請問這個位子被占了嗎？
As no pumas had been reported missing from any zoo in the country, this one must have been in the possession of a private collector and somehow managed to escape.
由于全國動物園沒有一家報告丟了美洲獅，因此那只美洲獅一定是某位私人收藏豢養的，不知怎么設法逃出來了。