The four forms of a verb are:
Base form
(also known as infinitive): This is the form of the verb that you would find in the dictionary, and it is the form that does not change regardless of the subject or tense. For example, "to walk" is the base form of the verb "walk."
Past tense:
This is the form of the verb that shows that the action happened in the past. It is usually formed by adding "-ed" to the base form of regular verbs. For example, "walked" is the past tense of "walk."
Past participle:
This is the form of the verb that is used in perfect tenses and passive voice. It is usually formed by adding "-ed" to regular verbs, but irregular verbs have their own unique past participles. For example, the past participle of "walk" is "walked."
Present participle
(also known as gerund): This is the form of the verb that ends in "-ing." It is used as a noun in sentences, and it can also be used as a modifier. For example, "walking" can be used as a subject in a sentence, as in "Walking is good for your health," or it can be used as a modifier, as in "The walking trail is beautiful."
Some common verbs and their four forms:
- Walk - walk, walking, walked, walked
- Eat - eat, eating, ate, eaten
- Run - run, running, ran, run
- Speak - speak, speaking, spoke, spoken
- Write - write, writing, wrote, written
- Sing - sing, singing, sang, sung
- Swim - swim, swimming, swam, swum
- Drive - drive, driving, drove, driven
- Drink - drink, drinking, drank, drunk
- Break - break, breaking, broke, broken
- Choose - choose, choosing, chose, chosen
- Fly - fly, flying, flew, flown
- Give - give, giving, gave, given
- Know - know, knowing, knew, known
- See - see, seeing, saw, seen
- Take - take, taking, took, taken
- Think - think, thinking, thought, thought
- Wear - wear, wearing, wore, worn
- Speak - speak, speaking, spoke, spoken
- Read - read, reading, read, read
Note that irregular verbs like "eat," "speak," and "write" have unique past tense and past participle forms that do not follow the usual "-ed" pattern of regular verbs.