- Present tense expresses an action that is present - going on at the moment. Example: Yesterday, I played outside.
- Past tense is the tense which expresses the action that has past - previously existed. Example: I play outside.
- Future tense is the tense which expresses an action that hasn't happened yet. Example: Tomorrow I will play outside.
The tense structure is the order in which the components go in a sentence. These are subjects, object, verbs, auxiliary verbs, etc. This structure tells the reader which tense the sentence is in.