_ unsolved, the problem of foodsafety may lead to more serious results

solve the problem, thelittle boy turned to his f

Hearing her only son killed in the accident, the old woman ________ her face in her hands and cried.[ ]

填入横线上的句子，与上文衔接最恰当的一句是（ ）随着市场经济体制的日臻完善，利用先进技术提高产品的科技含量以增强市场竞争力，已成为各企业集团的共识。_________________________________________ 。

“How did the robber get in?”—-“______ an open window on the first floor.”