単位換算（unit_convert）

Length, meters, kilometers, miles, yards, feet, inches, ri, while, long
It weighs, transmural, catty, grams, kilograms, ounces, pounds, tons (UK), tons (US) ...
The area, basis, counter, town, square meters, Earl, square kilometers, acres ...
Other, volume, and at once conversion pressure, the energy or the like.