
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
Taxi driver Lao Wang passes through six traffic checkpoints on his way from the restaurant to the train station, and it is known that the traffic lights at each checkpoint are independent of each other. Assuming that the probability of encountering a red light at each checkpoint is $\frac{1}{3}$, calculate the probability that he has passed two checkpoints before encountering a red light.

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