（ ） refers to the channel on a steep slope, and it is also known as the suspended ditch. A: Chute B: side ditches C: seepage ditch D: underdrain

Fill in the blanks with the expressions given below. Change the form where necessary. Each expression can be used only once.4.The ditches (沟) were 4)____mud and garbage again after the pouring rain.

①When I was a boy growing up off the grid in the Commonwealth of Virginia, the men I knew labored with their bodies from the first rooster crow in the morning to sundown. ②They were marginal farmers, shepherds, just scraping by, or welders, steelworkers, carpenters; ③they built cabinets, dug ditches, mined coal, or drove trucks, their forearms thick with muscle. ④They trained horses, stocked furnaces, made tires, stood on assembly lines, welding parts onto refrigerators or lubricating car engines. ⑤In the evenings and on weekends, they labored equally hard, working on their own small tract of land, fixing broken-down cars, repairing broken shutters and drafty windows. ⑥In their little free time, they drowned their livers in beer from cheap copper mugs at a bar near the local brewery or racecourse. (Para.1) ①The bodies of the men I knew were twisted and wounded in ways visible and invisible. ②Heavy lifting had given many of them spinal problems and appalling injuries. ③Some had broken ribs and lost fingers. ④Racing against conveyor belts had given some ulcers. ⑤Their ankles and knees ached from years of standing on concrete. ⑥Some had partial vision loss as the glow of the welding flame damaged their optic receptors. ⑦There were times, studying them, when I dreaded growing up. ⑧All around us, the fathers always seemed older than the mothers. ⑨Men wore out sooner, being martyrs of constant work. ⑩Only women lived into old age. (Para.2) ①There were also soldiers, and so far as I could tell, they scarcely worked at all. ②But when the shooting started, many of them would die for their patriotism in fields and forts of foreign outposts. ③This was what soldiers were for - they were tools like a wrench, a hammer or a screw. (Para.3) These weren't the only destinies of men, as I learned from having a few male teachers, from reading books and from watching television. But the men on television - the news commentators, the lawyers, the doctors, the politicians who levied the taxes and the bosses who gave orders - seemed as remote and unreal to me as the figures in old paintings. I could no more imagine growing up to become one of these sophisticated people than I could imagine becoming a sovereign prince. (Para.4)