Question

I have been living in the United States for twenty years, but seldom _____ so lonely as now．

A．have I felt

B．I had felt

C．I have felt

D．had I felt

Answer 1

A

考查倒装句。否定词放在句首，使用部分倒装，题中的否定词为seldom，根据时态应用完成时态，所以助动词have 提前，选A。