When the author said "he was lucky", it means the following except ______.A.the topic he f
When the author said "he was lucky", it means the following except ______.
A.the topic he found in a book a century ago is so strange
B.he often finds that the past has valuable lessons for the future
C.there are many books on electric vehicles in the 20th century
D.books published before 1923 are in the public domain