Melissa Rauch plays Howard Wolowitz' girlfriend (now wife), Bernadette.
Melissa Rauch plays Howard's wife on The Big Bang Theory.
Carol Ann Susi
He's a mechanical engineer at Cal Tech, specializaing in gear used in outer space.
The Big Bang Theory episode where Sheldon Cooper plays the theremin is entitled The Bus Pants Utilization.
Sheldon Cooper does have a girlfriend on The Big Bang Theory. His girlfriend's name is Amy Farah-Fowler, played by Mayim Bailik. Their relationship was made official in the episode "The Flaming Spittoon".
Melissa Rauch
Carol Ann Susi plays the voice of Howard Wolowitz's mother on The Big Bang Theory. She is only heard, never seen.
Carol Ann Susi plays Howard's mom on The Big Bang Theory, tho she is never seen. We only hear her voice.
Alice Amter plays Mrs. Koothrappali.
Johnny Galecki
Siri was played by Becky O'Donohue.
Priya is portrayed by Aarti Mann