Direction: The following question consists of fragments of a sentence. The first fragment (1) and the last fragment (6) are in order. The other four fragments are jumbled up and are designated as (P), (Q), (R) and (S). Find out the correct sequence of these from the given alternatives.  

1. When I reached my office

P. to get home early

Q. I phoned my mother

R. that I wouldn't be able

S. to tell her

6. as I had promised.