21. “______” is not euphemistic expression in English for lavatory.（      ）

A. Comfort station                                        B. To be patient

C. To relieve oneself                                     D. To wash one’s hands

22．“Tickets, please!” said the guard, putting his head in at the window. In a moment everybody was holding out a ticket.

The example above demonstrates ______ relation between the two sentences.（      ）

A. a temporal                                               B. a causal

C. an additive                                               D. an adversative

23．The British English equivalent for “公立學(xué)�！� is ______.（      ）

A. public school                                           B. council school

C. private school                                          D. grade school

24. “I’m full” is signified in English culture by ______.（      ）

A. an open hand, palm down, raised to one’s throat

B. one or both open hands lightly patting one’s own stomach

C. a raised open hand, palm forward

D. moving quickly his open hand, palm down, across his throat