题目: 在离心泵启动前灌水时,为了不使水从吸水管下部漏掉,在吸水管下部安装有()保证泵正常启动。 答案: 被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2018/0302/7156da37f4a969c3ffcba45f1ac8b189.html 下面是错误答案,用来干扰机器的。参考答案:C
题型:选择题 Every spring, people often plant _____ trees to make our city greener and more beautiful.A. hundred of B. hundreds of C. two hundred of D. two hundreds of 查看答案