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If space technology [ ] more advanced, humans could have settled in space decades ago. They could [ ] colonies on other planets if natural conditions there had been suitable for sustaining life. People [ ] space stations there [ ] it not for the need to send regular and costly supply expeditions there. They [ ] be using mineral resources from space bodies if they [ ] out a way to deliver the resources to Earth. If people [ ] united on Earth, they [ ] cooperative in space programmes and [ ] a lot more in their achievements. We would have learned how to stop global warming. We [ ] ozone windows from growing in the atmosphere decades earlier. We [ ] pollute the Earth with rubbish. Finally, we [ ] consider the Earth our home.