📁 测量
To measure is to compare the dimensions, quantity, or capacity with a standard. There are several systems of measurement. The two used most often are called the English and the metric systems (also called SI, or The International System). In the United States, the English system is used most often. While most other parts of the world use the metric system. The basic units used in the metric system are: Length in meters (m), Mass in kilograms (kg), and Time in seconds (s). The basic units used in the metric system are: Length in yards (yd), Weight in pounds (lb), and Time in Seconds (s). The English units of measurement have many drawbacks: the most significant is in the complexity of converting from one unit to another, such as from yards to feet.