A - Bildung

Das past continuous bildet man mit:
were oder was (simple past von "be") +  -ing
	
B -Gebrauch

Das past continuous bezeichnet eine Handlung,
die gerade in der Vergangenheit stattfindet
(z.B. Erzählung).

Beispiel:	When he arrived, I was cooking.
					What were you doing up so late at night?