---I don’t think sixteen-year-olds _______ to drive.---I agree. They aren’t serious enough at that age.
Neil Armstrong is the first man .
They took rock samples back to Earth for _____study.
He went into space as _____polit of Gemini 8.
Yang Zhenyu ______ physics ever since he studied in Primary school.
Perhaps we will live in _________ dome on Mars.