
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Volunteers A and B, along with 5 other volunteers, participate in serving at four different positions A, B, C, and D at the Import Expo. Each person is assigned to one position, with at least one person at each position, and A and B cannot serve at the same position. How many different ways are there to participate? (Express your answer as a numerical value).

Present the answer in LaTex format: \boxed{Your answer}
user