摘要：
Outing 题目描述 Organising a group trip for the elderly can be a daunting task... Not least because of the fussy participants, each of whom will only make 阅读全文
摘要：
Clock Pictures 题目描述 You have two pictures of an unusual kind of clock. The clock has n hands, each having the same length and no kind of marking whats 阅读全文