By definition, an accomplishment is something that has already happened. In other words, it happened in the past. This means that each bullet point should begin with a past tense verb. Powerful, active verbs deliver your message with a punch.
Finally, use a thesaurus and diversify your verbs. Repeating the same words can lower effectiveness, making your resume seem flat and redundant rather than persuasive. The following resume job description examples illustrate all of these suggestions in practice.