1.I ____to go for a walk,but someone called and I couldn't g

1.I ____to go for a walk,but someone called and I couldn't get away.A.was planning B.planned C.had planned D.would plan 但为什么不能选A?2.----We are informed that the Weifang International Kite Festival starts at 7:00.----Oh,I didn't expect it was so early!I ____to go out for dinner with my friends first.A.was planning B.am planning C.have been planning D.have planned 与上题比较,同样的问题,为啥又不选D了?