可能是尿路结石引起的腹痛是
A.暗红色果酱样脓血便B.排便前后有鲜血滴出或喷射出C.黏液脓性鲜血便D.粪便灰黑色,无光泽E.洗肉水样粪便伴腥臭味
参考答案:C
Many people think it’s very difficult to ______ a conversation with someone who only says “Yes” and “No”.
A.break off
B.focus on
C.keep up
D.listen to
用政府管制迫使自然垄断收取的价格等于其边际成本将()
A.提高效率。
B.提高物品价格。
C.吸引企业进入市场。
D.引起垄断者退出市场。