user: ### NOW ANSWER:
Question: What is Years, when Nationality is United States, and when Position is PG / SG?
Columns: ['Player', 'Nationality', 'Jersey Number(s)', 'Position', 'Years', 'From']
Types: ['text', 'text', 'real', 'text', 'text', 'text']
Sample row: ['Mark Radford Category:Articles with hCards', 'United States', 30.0, 'PG / SG', '1981 – 1983', 'Oregon State']
SQL:

assistant: SELECT "Years" FROM "Table" WHERE "Nationality" = 'United States' AND "Position" = 'PG / SG';