2, the stream is brave, not afraid of the obstacles of mountains, not afraid of the rugged road under your feet, and bravely go forward; The tree is strong, it is not afraid of the storm, not afraid of the torture of cold and heat, standing tall and straight. Lighthouses are fearless. It is not afraid of endless darkness. It is not afraid of years of loneliness.
3, maternal love is a ray of sunshine, so that your heart can feel warm as spring even in the cold winter; Motherly love is a clear spring, which makes your feelings pure even in the dust of years. Motherly love is a breeze, even if it is shrouded in haze, it can restore your mood to clear Wan Li.
Extended data:
Many ancient scientists, in order to understand the nature of a thing, often compare it with known things qualitatively, that is, they have many similar properties, thus inferring that these two things have other similar properties.
For example, in order to understand the spread of sound, Song, an ancient scientist in China, wrote in On Qi: "Force: the power of things is like the power of water. When the stone enters the water, the water touches the stone and the punch stops. Its waves open from time to time, its search for text is endless, and its arrogance is also awkward. "
Here, Song compared the sound of knocking with the ripples of stones throwing water. Because water travels in the form of waves, so can sound. Song used qualitative analogy here to infer that sound propagates in the form of waves in the air.