A-A+
With the introduction of the electronic comput
问题详情
With the introduction of the electronic computer, there is no complicated problem can be solved in a few hours.
A．but
B．which
C．that
D．what
参考答案
正确答案：A
解析：but在英语句子中可用作关系代词，引导定语从句。但应特别注意but虽然形式上是肯定的，意义上却是否定的。这正是but和其它关系代词(who，that，which等)不同之处。
