1. His touch on the piano is very certain. (그의 피아노의 터치는 정확하다) 2. I am certain of his succeeding. (그의 성공은 확실하다고 생각한다) 3. They are certain to need help. (그들에게는 원조가 꼭 필요하다) 4. She was certain that the young man had gone mad. (그녀는 그 젊은이가 미친 것이 틀림없다고 생각했다) 5. feel certain (확실하다고 생각하다)
