original passage: Lateral undulation is the sole mode of aquatic locomotion, and the most common mode of terrestrial locomotion. In this mode, the body of the snake alternately flexes to the left and right, resulting in a series of rearward-moving "waves". While this movement appears rapid, snakes have rarely been documented moving faster than two body-lengths per second, often much less. This mode of movement has the same net cost of transport (calories burned per meter moved) as running in lizards of the same mass.
original sentence: While this movement appears rapid, snakes have rarely been documented moving faster than two body-lengths per second, often much less.
sentence2: Can a student determine the speed of a viper from information obtained from library books?
sentence1: Lateral undulation is the sole mode of aquatic locomotion, and the most common mode of terrestrial locomotion. In this mode, the body of the snake alternately flexes to the left and right, resulting in a series of rearward-moving "waves". This movement appears rapid, snakes have been documented moving faster than two body-lengths per second, rarely much less. This mode of movement has the same net cost of transport (calories burned per meter moved) as running in lizards of the same mass.