Verbs that do not change form

The irregularity in English language cause change in verbs to be varied. In past tense or present continuous. some verb change completely and some only change letters in the middle. Below is the an example of a verb that do not change it's form in past tense nor present continuous. 

 

Play the exercise for lesson 2 to see your understanding http://www.turtlediary.com/grade-3-games/ela-games/regular-and-irregular-verbs.html