Lack of agreement (or match) between subject and verb
Make sure you employ the correct verb form for a given sentence/situation:
He sat out the entire game because he had broke his big toe.
Problem and cure: The word "had" indicates that the verb should be the past participle of "break," which is "broken."
There is no way to account for the thousands of different verb forms. An understanding of them takes practice and patience. Non-native speakers of English often have trouble learning when and how to use what verbs, but it is a common problem in all student writing.