Final answer:
To change the sentence 'In the meantime, the ISS is being built by people from 16 countries' to the active voice, it should be rewritten as 'In the meantime, people from 16 countries are building the ISS.' This positions the people as the subjects who perform the action of building.
Step-by-step explanation:
To change the verb from passive to active voice in the sentence 'In the meantime, the ISS is being built by people from 16 countries,' we need to make the people from the 16 countries the subject of the sentence who are carrying out the action. Therefore, the active voice version of the sentence is 'In the meantime, people from 16 countries are building the ISS.' When converting from passive voice to active voice, it's important to establish who is performing the action and to position them as the subject of the sentence. This creates a sense that those individuals are the ones directly carrying out the action. In contrast, passive voice sentences often place the subject as the recipient of the action and can lack clarity.