Sắp xếp các từ để tạo ra câu hoàn chỉnh

1. Jack / video conference / his colleagues / in Asia / at the moment.

2. He / say / he / do well / science / school / then.

3. Nick / ask / the professor / why / humans / not live / Mars.

4. Robots / replace / humans / 30 years' time.

5. Many students / ask me / what / differences / Mars and Earth / be.