There are two important cases : ( i ) a simple closed chain and ( ii ) a simple open chain .
There are two important special cases : ( i ) a simple open chain , and ( ii ) a simple closed chain .
There are two important special cases : ( i ) a simple open chain , and ( ii ) a simple closed chain .
이 텍스트 다시 쓰기: There are two important cases : ( i ) a simple closed chain and ( ii ) a simple open chain . 산출: