注意：此页面搜索的是所有试题
题目内容
（大连工业大学-大学英语2）
(单选题) By the time he was 12, Edison ______ to make a living by himself. ( )(本题3.0分)
A、 would begin
B、 has begun
C、 had begun
D、 was begun
A、 would begin
B、 has begun
C、 had begun
D、 was begun
参考答案