Add hyphens to compound adjectives where necessary. If no hyphens are needed , submit the text without making any changes. Joseph Priestley is well known for his discovery of oxygen, but he also invented carbonated water and the rubber eraser .

## Step 1<br />Identify the compound adjectives in the sentence. A compound adjective is a combination of two or more words that function as an adjective in a sentence. These words are usually hyphenated to avoid confusion.<br /><br />## Step 2<br />In the sentence, "Joseph Priestley is well known for his discovery of oxygen, but he also invented carbonated water and the rubber eraser", the compound adjectives are "well-known" and "rubber eraser".<br /><br />## Step 3<br />The compound adjective "well-known" is used to describe Joseph Priestley. It is a combination of the adverb "well" and the adjective "known", which together describe the degree to which Priestley is known.<br /><br />## Step 4<br />The phrase "rubber eraser" is not a compound adjective, but a noun phrase. It consists of two nouns, "rubber" and "eraser", which are used together to describe a type of eraser.