certain

adj. ①确实，肯定 ②确定，无疑③某位，一位叫……的

【搭配】for a certain reason由于某种原因

for certain肯定，确定，无疑

be certain of/about确信，深信

be certain to do sth．肯定会

It is certain that…肯定会，确实

make certain（ that...）弄清楚，弄明白：We went to the theatre early and made certain （that） we all got seats.