“Thats one small step for a man, one giant leap for mankind.” During NASAs Apollo program, 12 American astronauts explored the lunar terrain. The last U.S. trip to the moon (30) ______ in December 1972. -------------------- Bạn hãy đọc đoạn văn trên và trả lời câu hỏi. “We will return to the moon no later than 2020 and extend the human presence across the (28) _____ system and beyond,”