I can maintain polite conversation.
There are skid marks in front of the dog.
You can tuna piano, but you can't piano a tuna!
An erection can make it past the semis, and still stand up if you sing for it.
The ring bearer had an erection.
Because none of their readers believe them when they receive a warning that it's their final issue.
One costs a lot of money to maintain, keep running, and give you the results you want. The other has four wheels.