单项选择题
中水管道与生活饮用水管道、排水管道平行埋设时，其水平净距为( )m。A.≮0.3B.≮0.5C.≮0.7D....
单项选择题中水管道与生活饮用水管道、排水管道平行埋设时，其水平净距为( )m。
Once Johnny starts painting a picture, he won′t stop un...
单项选择题Once Johnny starts painting a picture, he won′t stop until it_________
George ought to have arrived_________this time.A.during...
单项选择题George ought to have arrived_________this time.
