GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - ZE06EG3QR3EC5X69K

A law has been proposed requiring the cargo boxes of trucks carrying gravel to be covered by a tarpaulin, because vehicles driving close behind open-topped gravel trucks can be damaged by gravel flying off these trucks. The law is unlikely to substantially reduce such damage, however: flying gravel is much less likely to come from the cargo box itself than from the grooves of the tires, in which gravel can become wedged during loading.