U-3：up a tree 在困难中
A:I met Mark yesterday. He looked blue.
A:昨天我遇到了马克，他着起来很忧郁。
B:He's been on the gravy train these years, hasn't he?
B：这几年他不是一直很走运吗？
A:It belongs to the past. He lost his job the other day, and he's up a tree now.
A:那是过去的事了，前几天他失业了，现在他正处在困难中。
B:It seems that nobody can always expect things to pan out well each time.
B：看来每个人都别期望自己总是一帆风顺呀！
