题干
It's reported that at least one Chinese vessel________in the hands of attackers in Somalia so far.
A：had bee
B：has bee
C：wa
D：i
答案(点此获取答案解析）
B
A：had bee
B：has bee
C：wa
D：i
，则a与0的大小关系是a 
，则a与0的大小关系是a