食管癌中晚期最突出的症状为( )
A．哽咽感 B．贫血C．进行性吞咽困难 D．胸骨后针刺样疼痛或烧灼感
参考答案：C
The number of people invited to the party _____ sixty, but a number of them ______absent.
A．were; was
B．was; was
C．was; were
D．were; were
未装防误闭锁装置或闭锁装置失灵的刀闸手柄和网门必须_____。
