English Tenses Overview

Present Tense
- Simple Present: Indicates habitual actions (e.g., She walks).
- Present Continuous: Ongoing actions (e.g., She is walking).
- Present Perfect: Actions that occurred at an unspecified time (e.g., She has walked).
- Present Perfect Continuous: Actions that started in the past and continue (e.g., She has been walking).
Past Tense
- Simple Past: Completed actions (e.g., She walked).
- Past Continuous: Actions that were ongoing in the past (e.g., She was walking).
- Past Perfect: Actions completed before another past action (e.g., She had walked).
- Past Perfect Continuous: Duration of an action up to a point in the past (e.g., She had been walking).
Future Tense
- Simple Future: Actions that will happen (e.g., She will walk).
- Future Continuous: Ongoing actions that will occur in the future (e.g., She will be walking).
- Future Perfect: Actions that will be completed before a certain point in the future (e.g., She will have walked).
- Future Perfect Continuous: Duration of an action leading up to a future point (e.g., She will have been walking).

Definition: Auxiliary verbs that express ability, possibility, necessity, or permission.
Common Modals:
- Can: Ability or possibility (e.g., She can swim).
- Could: Past ability or polite request (e.g., Could you help me?).
- May: Permission or possibility (e.g., You may leave).
- Might: Less certain possibility (e.g., It might rain).
- Must: Necessity or strong recommendation (e.g., You must study).
- Should: Advice or suggestion (e.g., You should exercise).
- Will: Future intention (e.g., I will call you).
- Would: Polite request or hypothetical situation (e.g., I would go if I could).

Definition: The subject and verb in a sentence must agree in number (singular or plural).
Basic Rules:
- Singular subjects take singular verbs (e.g., The cat runs).
- Plural subjects take plural verbs (e.g., The cats run).
Compound Subjects:
- Joined by 'and': Use a plural verb (e.g., The dog and cat play).
- Joined by 'or/nor': The verb agrees with the nearest subject (e.g., Either the dog or the cats are out).
Indefinite Pronouns:
- Some are always singular (e.g., everyone, each) and take singular verbs (e.g., Everyone is here).
- Some are always plural (e.g., few, many) and take plural verbs (e.g., Many are called).
Collective Nouns: When referring to a group as a single unit, use a singular verb (e.g., The team wins). If emphasizing individual members, use a plural verb (e.g., The team are wearing their uniforms).

Present Tense is used for actions happening now or regularly.
Simple Present indicates habitual actions (e.g., "She walks").
Present Continuous describes ongoing actions (e.g., "She is walking").
Present Perfect refers to actions that occurred at an unspecified time (e.g., "She has walked").
Present Perfect Continuous indicates actions starting in the past and continuing (e.g., "She has been walking").
Past Tense refers to actions that have been completed.
Simple Past denotes completed actions (e.g., "She walked").
Past Continuous shows actions ongoing in the past (e.g., "She was walking").
Past Perfect refers to actions completed before another past action (e.g., "She had walked").
Past Perfect Continuous emphasizes the duration of an action before a specific past point (e.g., "She had been walking").
Future Tense indicates actions that will take place.
Simple Future covers actions that will happen (e.g., "She will walk").
Future Continuous illustrates ongoing actions in the future (e.g., "She will be walking").
Future Perfect indicates actions that will be completed by a certain future point (e.g., "She will have walked").
Future Perfect Continuous shows the duration of an action leading up to a future moment (e.g., "She will have been walking").

Modals are auxiliary verbs expressing ability, possibility, necessity, or permission.
"Can" signifies ability or possibility (e.g., "She can swim").
"Could" indicates past ability or is used for polite requests (e.g., "Could you help me?").
"May" denotes permission or possibility (e.g., "You may leave").
"Might" suggests a less certain possibility (e.g., "It might rain").
"Must" conveys necessity or a strong recommendation (e.g., "You must study").
"Should" provides advice or suggestions (e.g., "You should exercise").
"Will" expresses future intention (e.g., "I will call you").
"Would" indicates a polite request or hypothetical situations (e.g., "I would go if I could").

Subject-Verb Agreement ensures subjects and verbs match in number (singular or plural).
Singular subjects take singular verbs (e.g., "The cat runs").
Plural subjects utilize plural verbs (e.g., "The cats run").
Compound subjects joined by 'and' require a plural verb (e.g., "The dog and cat play").
For compound subjects joined by 'or/nor', the verb agrees with the nearest subject (e.g., "Either the dog or the cats are out").
Indefinite pronouns can be singular (e.g., "everyone," "each") taking singular verbs (e.g., "Everyone is here") or plural (e.g., "few," "many") requiring plural verbs (e.g., "Many are called").
Collective nouns usually take a singular verb when referring to a group as a single unit (e.g., "The team wins") but take a plural verb when emphasizing individual members (e.g., "The team are wearing their uniforms").