Woman in red cardigan: People do get their tenses of a verb confused. Making sure that the verb is in the same tense all the way through a document or a letter or an email. If you read it to ...

When you are writing, you can use words that show if the events have already happened, are happening now or will happen in the future. The past tense is used for things that have already happened.

Modal verbs, which express a likelihood, ability, permission, request, order etc., usually help main verbs to state the future. It is the reason they are categorised as auxiliary verbs in the context.