This page provides an overview of important modal verbs and tenses in English, focusing on their usage and conjugation. It covers concepts crucial for expressing ability, permission, and obligation across different time frames.

The page begins by listing common modal verbs:

• can
• may
• must
• needn't

Vocabulary: Modal verbs are auxiliary verbs that express meanings such as ability, possibility, permission, or obligation.

Next, it introduces two important phrases:

• (to) be able to
• (to) be allowed to

Example: "I'm able to walk." (present tense) "I was able to walk." (past tense) "I will be able to walk." (future tense)

These examples demonstrate how "be able to" can be used in different tenses to express ability.

Similarly, examples are provided for "be allowed to":

Example: "I'm allowed to visit you." (present) "I was allowed to visit you." (past) "You will be allowed to visit us." (future)

The page then introduces the concept of obligation with "have to":

Example: "I have to learn my vocab." (present) "I had to learn my vocab." (past) "I will have to learn my vocab." (future)

Highlight: The negative form of "have to" is "not (to) have to," as in "I don't have to cook."

Finally, the page lists signal words that indicate different tenses:

• Present: now, at the moment, always, sometimes, usually, normally
• Past: yesterday, ago, last
• Future: tomorrow, in a few days, next...

Definition: Signal words are time expressions that help identify the tense of a sentence.

This comprehensive overview helps students understand how to use modal verbs and express different time frames in English, which is crucial for mastering English grammar and improving language skills.