Reported Speech, Conditionals and Passive Voice: Complete English Grammar Guide

Present Simple => Past Simple: I train => he said he trained
Present Continuous => Past Continuous: I'm having => he said he was having
Present Perfect => Past Perfect: We haven't seen it => they said they hadn't seen it
Past Simple => Past Perfect: I met her => he said he had met her
Can => Could / Will => Would / Must => Had to / May => Might
Said to me / Told me
Expressions: This => That / Here => There / Today => That day / Yesterday => The day before / The previous day / Tomorrow => The next day / The following day

Conditionals

Type 0 and Type 1

* Present + Present: universal truths or things that are always true:
Si calientas mantequilla se derrite. / If you heat butter, it melts.

* Present + Imperative:
Si tienes calor, abre la ventana. / If you are hot, open the window.

* Present + Future:
Si estudias, aprobarás. / If you study, you will pass.

Type 2: Possible situations (unlikely or hypothetical)

* Past Simple + Conditional Simple:
Si tú estudiaras, tú aprobarías. / If you studied, you would pass.

Type 3: Impossible situations (past, cannot be changed)

* Past Perfect + Conditional Perfect:
Si tú hubieras estudiado, habrías aprobado. / If you had studied, you would have passed.

Active and Passive Voice

Present and Past Tenses

Present Simple: This singer writes many songs. → Many songs are written by this singer.

Past Simple: This singer wrote many songs. → Many songs were written by this singer.

Present Continuous: This singer is writing many songs. → Many songs are being written by this singer.

Past Continuous: This singer was writing many songs. → Many songs were being written by this singer.

Future and Perfect Tenses

Future Simple: This singer will write many songs. → Many songs will be written by this singer.

Present Perfect Simple: This singer has written many songs. → Many songs have been written by this singer.

Past Perfect Simple: This singer had written many songs. → Many songs had been written by this singer.

Be going to: This singer is going to write many songs. → Many songs are going to be written by this singer.

Modal Verbs

Modals: This singer should write many songs. → Many songs should be written by this singer.

Modal Perfects: This singer must have written many songs. → Many songs must have been written by this singer.

Have to: This singer has to write many songs. → Many songs have to be written by this singer.