For example, did you know that 1 in 4 teenagers has tried marijuana?
比如,你是否知道4个青少年中就有1位曾经吸过大麻?
So far, no man has travelled farther than the moon, but spaceships without people have reach other parts of the universe.
到目前为止,尚未有人到过比月球更远的地方,但无人驾驶的宇宙飞船已到达过宇宙的其它地方。