早期妊娠的诊断，下列哪项最为准确
A．停经伴恶心、呕吐B． * * 充血变软，呈紫蓝色C．子宫增大D．B超探及胎心管搏动E．自觉胎动
参考答案：D
广州西关著名的上下九步行街在（）年建成
A、1994
B、1995
C、1996
Mr Bush is on time for everything. How _______ it be that he was late for the opening ceremony?
A．can
B．should
C．may
D．must
