Final answer:
Speech codes indeed help in understanding, predicting, and controlling communication by providing frameworks to interpret interactions.
Step-by-step explanation:
The statement that speech codes can be used to understand, predict, and control communication is true. Speech codes are sets of communication patterns that are culturally informed and can provide us with a framework to interpret interactions in social contexts. Being aware of these patterns facilitates predicting how individuals might behave in communication scenarios and, to some extent, allows for the control of discourse to achieve desired outcomes.