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(truck) load-carrying tray; (bicycle) luggage carrier; roof rack
荷台に荷物を積んだ。
I loaded cargo onto the truck bed.
軽トラの荷台で材木を運んだ。
I hauled lumber in the back of a kei truck.
子供を自転車の荷台に乗せてはいけない。
You shouldn't put children on the bicycle rack.