Complex sentence: She gained national prominence with "My Friend Irma" on radio, television and film and played the quintessential dumb blonde, appearing in numerous comedies and in Ken Murray's famous Hollywood "Blackouts".
Split into simpler sentences: She gained national prominence with "My Friend Irma" on radio, television and film. She portrayed the quintessential dumb blonde in numerous comedies and in Ken Murray's famous Hollywood "Blackouts".