General Rule:
* "-able" is added to the base form of the verb to create an adjective that means "capable of being [verb]".
Examples:
* Break + -able = breakable (capable of being broken)
* Change + -able = changeable (capable of being changed)
* Understand + -able = understandable (capable of being understood)
Exceptions and Considerations:
* Irregular Verb Forms: Some verbs have irregular past participles, and you'll need to use those forms when adding "-able." For example: "do" becomes "doable" because the past participle is "done."
* Meaning Changes: Sometimes, adding "-able" can shift the meaning of the verb slightly. For instance, "use" becomes "usable", which implies something is suitable for use, not just capable of being used.
* Phrasal Verbs: With phrasal verbs (verbs with prepositions or adverbs), adding "-able" can be tricky. Sometimes it works, like "take off" becomes "takeable off," but often it doesn't sound natural.
* Grammar Rules: Not every verb can be transformed into an adjective with "-able." The verb must express a state or potential, not necessarily an action.
Overall:
While adding "-able" to a verb is generally possible, it's important to consider the nuances of the verb's meaning and the resulting adjective's grammatical correctness.