Essential English Grammar: Conditionals and Passive Voice

English Conditional Sentences

• 1st Conditional (Realidad): If/Unless + Subject + Present Simple + Complement, Subject + Future Will + Complement.
• 2nd Conditional (Imaginación): If + Subject + Past Simple + Complement, Subject + Conditional (Would) + Complement.
• 3rd Conditional (Imposible): If + Subject + Past Perfect + Complement, Subject + Perfect Conditional (Would Have) + Complement.

Reported Speech (Estilo Indirecto)

Sentence Types

• Enunciativas: Subject + said + that...
• Commands (Tell/Mandar): Subject + told + pronoun + (not) + to + infinitive + Complement.
• Requests: Same as commands, but replace told with asked.

Reporting Verbs

• Ordered (mandar), Invited (invitar), Convinced (convencer): Verb + pronoun + to + infinitive + Complement.
• Refused (rechazar/negarse a), Agreed (estar de acuerdo/aceptar), Offered (ofrecer): Verb + to + infinitive + Complement.
• Complained (quejarse), Explained (explicar), Admitted (admitir), Insisted (insistir): Verb + that + Subject + Verb + Complement.

Questions in Reported Speech

• Yes/No Questions: If/Whether + Subject + Verb + Complement.
• Wh- Questions: Interrogative pronoun + Subject + Verb + Complement.

Word Transformations

• Pronouns: I (he/she), we (they), you (I/we), my (his/her), our (their), you (my), mine (his/hers), ours (theirs), yours (mine), us (them).
• Time and Place: Now (then), today (that day), tonight (that night), yesterday (the day before), tomorrow (the day after), last.../a... ago (the previous...), next... (the... after), this (that), these (those), here (there).

Tense Changes

• Present Simple: Becomes Past Simple.
• Present Continuous: Becomes Past Continuous.
• Past Simple / Present Perfect: Becomes Past Perfect.
• Future Will: Becomes Conditional Would.
• Be going to: Becomes Be going to (Past Simple).
• Can: Becomes Could.
• Must: Becomes Had to.

Passive Voice (Pasiva)

• Present: Am/Is/Are + past participle.
• Past: Was/Were + past participle.
• Future: Will be + past participle.
• Structure: Subject + Verb + Direct Object + Complement → Subject (Direct Object) + Verb (Passive) + Complement + Agent (Subject).

Modal Verbs

Ability

• Can (Present): Poder/Saber. Can/Can't + infinitive; Can + Subject + infinitive?
• Could (Past): Poder/Saber.
• Will be able to (Future): Poder/Saber. Will + Subject + be able to + infinitive?

Possibility, Advice, and Obligation

• Possibility: May/Might (puede que). May/Might + infinitive; May/Might not + infinitive; May/Might + Subject + infinitive?
• Advice: Should (debería).
• Obligation: Must (deber/tener que) or Have to (tener que). Have/Has to + infinitive; Don't/Doesn't have to + infinitive; Do/Does + Subject + have to + infinitive?

Indefinite Pronouns

• Every (Todo): Everybody/Everyone, everything, everywhere.
• No (Nada/Nadie): Used in positive sentences.
• Any (Nada/Nadie): Used in negative and interrogative sentences.
• Some (Alguno): Used in positive sentences.

Quantifiers (Cuantificadores)

• So (Tan): So + adjective/adverb.
• Such (Tan): Such + Noun Phrase (SN).
• Too (Demasiado): Too + adjective/adverb.
• Enough (Suficientemente): Adjective + enough.
• Not enough (No suficientemente): Adjective + not enough.

Adverbs and Prepositions of Time

• Ever (Alguna vez): Have/Has + Subject + ever + past participle + Complement?
• Never (Nunca): Subject + have/has + never + past participle + Complement.
• Just (Acabar de): Subject + have/has + just + past participle + Complement.
• Still (Todavía): Subject + haven't/hasn't + past participle + Complement.
• Already (Ya): Subject + have/has + already + past participle + Complement.
• Yet (Todavía, ya): Subject + haven't/hasn't + past participle + Complement + yet; Have/Has + Subject + past participle + Complement + yet?
• For (Durante) and Since (Desde).