The document discusses various tenses in English grammar including the present indefinite tense, present continuous tense, and present perfect tense. It provides examples and explanations of when each tense is used. The key points covered are:
1. The present indefinite tense is used to describe present habitual or general truths, while the present continuous tense describes ongoing actions.
2. The present perfect tense is used for actions that began in the past and continue in the present, or actions that happened before now.
3. Examples and structures are given for each tense along with notes on their usage.