Question

fix any punctuation or capitalization errors below. click \submit answer\ if there are none.
richard watterson has a pinball machine in his living room; but he never lets me use it.

Explanation:

The semicolon before "but" is incorrect. "But" is a coordinating conjunction, and when joining two independent clauses, a comma should be used before it (or a semicolon can be used without the conjunction, but here with "but", a comma is appropriate). So we replace the semicolon with a comma.

Answer:

Richard Watterson has a pinball machine in his living room, but he never lets me use it.