He said that hard-working ________ the key ________ success.
He said that hard-working ________ the key ________ success.
A.was…to
B.will be…of
C.is…to
D.is being…of
答案及解析： C
He said that hard-working ________ the key ________ success.
A.was…to
B.will be…of
C.is…to
D.is being…of
答案及解析： C