Both selective mutism and an INABILITY
to separate from one's mother...
The Big Bang Theory Season 2, Episode 15
Your INABILITY
to successfully woo Penny...
The Big Bang Theory Season 1, Episode 14
...feigning an INABILITY to hear you
when you speak...
The Big Bang Theory Season 2, Episode 8
...the INABILITY to pass uri...
The Big Bang Theory Season 4, Episode 22
...and the INABILITY of some people
to follow the chain of command.
The Big Bang Theory Season 1, Episode 6