题目内容

在设有各类支架巷道中，巷道风流是指距支架和巷底各50mm的巷道空间内的风流。()

查看答案

搜索结果不匹配？点我反馈

更多问题

溜煤眼不得兼作进风眼。()

位于掘进工作面的局部通风机，其噪声不得超过85dB。()

使用3台局部通风机同时向1个掘进工作面供风，以满足风量要求。()

For this part, you are allowed 30 minutes to write A Letter to Apologize to your friend. You had an appointment with your friend on Sunday. Unfortunately you broke the appointment because your mother fell ill. Write a letter about 120 words to apologize for failing to keep the appointment. Your letter should follow the outline given below in Chinese:
1. 就失约向你的朋友道谦
2. 解释失约的原因
3. 建议另外约定一个时间