【题目】If you do fall out of the boat, your lifejacket will help you to ______ until we can fish you out.
A. stand up B. keep up
C. follow up D. stay up
在线课程【答案】D
【解析】句意：如果你真从船上掉下去了，救生衣就可帮助你漂浮在水面上，直到我们把你搭救上来。A. stand up站起来，坚持，竖立，站得住脚；B. keep up保持，继续，不低落，不落后；C. follow up跟踪，坚持完成，继续做某事；D. stay up熬夜，守夜，不倒，不沉。根据句意可知选D。