英語時態(tài)提問：大哥大姐們幫我看看下面這句話的時態(tài),搞不清楚了.
The inspector pointed out that on the morning of the murder,the 8 o'clock train did not run at all,as it had broken down at Ferngreen station and had been taken off the line.為什么：the 8 o'clock train did not run at all 不用過去完成時?為什么：as it had broken down at Ferngreen station and had been taken off the line.在主句使用一般過去時的情況下,從句使用過去完成時,主句和從句是同時發(fā)生的呀?