🔼SHOULD/ SHOULDN´T HAVE🔽

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Function: 

We use the perfect modal should / shouldn`t have to criticize or express regret about things that people did or didn`t do in the past.

Structure:

Should have + Past participle	I / he / She / We / you / they should have gone to the doctor.
Shouldn`t have + Past participle	I / he / She / We / you / they shouldn`t have been rude to the store assistant.

➽ SHOULD HAVE 1: Should have + past participle. 

1. We can use 'should have' to talk about past events that did not happen.
2. We can also use 'should have' to speculate about events that may or may not have happened.

Grammar:

It may mean something that would have been a good idea, but that you did not. It's like giving advice about the past when you tell someone else, or regretting what you did or did not do when you're talking about you.

Examples: 

1. She should have taken the children with her to Houston. (Ella debería haber llevado a los niños con ella a Houston)
   
2. He should have lent us the money which we need. (Él debería habernos prestado el dinero que necesitamos)
   
3. She should have been back by noon. (Ella debería haber regresado para mediodía)
4. She should have returned later. (Ella debería haber regresado más tarde)
5. You should have learnt at least five new words every day. (Tú deberías haber aprendido al menos cinco palabras cada día)

➽ SHOULDN'T HAVE 2: Shouldn't have + past participle. 

It means that something was not a good idea, but you did it anyway.

Grammar:

1. We can use 'shouldn't have' to speculate negatively on what may or may not have happened.
2. We can also use 'shouldn't have' to regret past actions.

Examples: 

1. You should not go by plane. (Tú no deberías ir en avión)
2. He should not save some money each week. (Él no debería ahorrar algo de dinero cada semana)
3. He should not pay more attention to what the teacher says. (Él no debería poner más atención a lo que dice el maestro)
   
4. It should not rain this evening. (No debería llover esta tarde)
   
5. We should not ask permission before doing it. (Nosotros no deberíamos pedir permiso antes de hacerlo)

➽ Exercices:

 Read these prayers of repentance and write the correct past participle verb:

• 1) I should have (buy) more water.
• 2) You should have (listen) to me.
• 3) I should not have (forget) my passport.
• 4) He should have (wear) a tie to the restaurant.
• 5) I should not have (eat) so much.
• 6) We should not have (drive) during the storm.
• 7) You should not have (hide) your sister's phone.
• 8) I should have (do) more research.
• 9) She should not have (drink) so much wine.
• 10) I should have (write) more.

For more information check the video link to clarify your doubts about the subject, thank you.