11-01. kilogram, kilograms.

[X is one kilogram.] = X is a weight. One thousand of these weights is the same as the weight of the water inside a container where the sides and bottom are each a square and the distance between two sides is one metre.

[The weight of most people is less than one hundred kilograms.]

11-02. sentence, sentences.

[X is a sentence.] = X is a small group of words that says one of these things: X can say something that is true or something that is not true. X can tell someone what you want them to do. X can say what you want someone to tell you.

[I wrote one sentence telling people not to give food to the animals.]

[I read a story containing more than one thousand sentences.]

[This sentence contains five words.]

11-03. cat, cats.

[X is a cat.] = X is an animal that has four legs and has hair covering its body. There are several different kinds of this animal: Some kinds are big, and some kinds are small. Many people enjoy having a small kind of this animal inside buildings where people live. X will find and eat other very small animals that people do not want inside buildings.

[I enjoy holding my cat and touching the hair that covers its body.]

[My cat held a small bird and ate it.]

11-04. sour.

[X tastes sour.] = X tastes like this: Many kinds of fruit taste like this before they become sweet and before most people want to eat them.

[When this fruit is green, it tastes sour, but when it becomes red, it tastes sweet.]

[The liquid inside this yellow fruit is sour, but when you mix a small amount of something sweet into this liquid, many people enjoy drinking it.]

Lisa has a white cat.

The weight of her cat __________.

• is five kilograms
• is more than five hundred kilograms
• is the same as five written sentences