Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What was the regular season standings for the year when the playoffs reached the conference semifinals and the team did not qualify for the US Open Cup?

### Inputs:
table_name: table, columns: ['Year', 'League', 'Reg. Season', 'Playoffs', 'US Open Cup', 'Avg. Attendance']

### Response:
SELECT Reg. Season FROM table WHERE Playoffs = Conference Semifinals AND US Open Cup = Did not qualify