9. I (walk) along the street when suddenly I (hear) footsteps behind me. Somebody (follow) me. I was frightened and I (start) to run.

I was walking along the street when suddenly I heard footsteps behind me. Somebody was following me. I was frightened and I started to run. *Объяснение:* Past Continuous (was walking) для действия, которое происходило в определенный момент, Past Simple (heard, started) для действий, произошедших внезапно или последовательно, и Past Continuous (was following) для описания действия, которое происходило в то же время, что и ходьба.