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?
When there is no one in the office, you can leave the answering machine on so that people who call you up can leave a message.
当无人在办公室时,你可以打开留言机,这样打电话给你的人就可以留言了。