Introduction:
The question is about how many people can cross the bridge at one time. This question is related to the topic of going to school and is in the Class 4 category.

Factors affecting the number of people:
There are several factors that can affect the number of people that can cross the bridge at one time. These factors include:

- The width of the bridge
- The strength of the bridge
- The weight of the people crossing the bridge
- The speed at which people are crossing the bridge
- The number of people crossing the bridge at the same time

Maximum number of people:
Based on these factors, it is difficult to determine an exact number of people that can cross the bridge at one time. However, it is generally recommended that people should cross the bridge in small groups to ensure safety.

Conclusion:
In conclusion, the number of people that can cross the bridge at one time depends on several factors, including the width and strength of the bridge, the weight of the people crossing, and the speed at which people are crossing. However, it is generally recommended that people cross the bridge in small groups to ensure safety.