Answer:
The development of cities is a complex process influenced by many factors. Based on the statements provided, the two that are generally true are:
"Cities thrive when a complicated road system helps people move around."
A well-developed infrastructure, including a comprehensive road system, is crucial for the growth of cities. It facilitates transportation, commerce, and the daily commute of residents, contributing to the overall functionality and appeal of the city.
"Cities thrive when their citizens participate in many different professions."
A diverse economy with citizens engaged in various professions contributes to the resilience and prosperity of a city. It allows for a broad range of services and industries, which can make the city more attractive to newcomers and more resilient to economic shifts.