【单选题】The keeper of the spring cleared away the leaves and branches, and wiped away the silt(淤泥) that would _______ have choked and polluted the fresh flow of water.
【简答题】阅读理解。 A plant (植物) makes its own food in its leaves, water comes to the leaves through the roots (根), air gets into the leaves through very small holes (孔), the green coloring in the leaves uses the w...