miércoles, 29 de marzo de 2017

HAVE TO, MUST, OUGHT TO, NEED & SHOULD



Modal Verbs of Obligation

We can use have to + infinitive, must + infinitive and should + infinitive to express obligation (something you have to do).
PresentPositiveNegative
have to /
don’t have to
strong obligation (possibly from outside)
  • Children have to go to school.
(sometimes ‘have got to’)
no obligation
  • I don’t have to work on Sundays.

  • You don’t have to eat anything you don’t like.
must / mustn’t strong obligation (possibly based on the speaker’s opinion)
  • I must study today.
negative obligation
  • You mustn’t smoke here.
should / shouldn’t mild obligation or advice
  • You should save some money.
mild negative obligation or advice
  • You shouldn’t smoke so much.
Be careful about the difference between mustn't and don't have to!
Mustn't
means it's not allowed, or it's a bad idea:
  • You mustn't eat so much chocolate, you'll be sick
Don't have to means you don't need to do something, but it's fine if you want to do it:
  • I don't have to get up early at the weekend
    (of course, if I want to get up early, that's fine, but I can stay in bed if I want
PastPositiveNegative
had to / didn’t have to obligation in the past
  • I had to go to wear a school uniform when I was a child.
no obligation in the past
  • We didn’t have to go to school on Saturdays.
must*changes to 'had to'-
should have + pp / shouldn’t have + pp a past action which didn’t happen: the advice / regret is too late
  • You should have gone to bed earlier, now you have missed the train.
a past action which didn’t happen: the advice / regret is too late
  • You shouldn’t have taken that job., it was a bad idea.

* Remember ‘must have done’ is a modal verb of deduction or speculation, not obligation in the past. For example: Julie must have left. Her coat’s not here.



EXERCISE ONE
EXERCISE TWO
EXERCISE THREE
 

Should, Ought to BY WWW.ECENGLISH.COM

For giving advice or expressing a conclusion 'should' and 'ought to' are interchangeable. They are used to express the same ideas.
You should/ought to stop smoking. He has been working on the project all week. He should/ought to be ready by this evening.
Should is also used in hypothetical situations: Should anyone call, take a message.
Call me should you need any help.

Should is used with 'imagine', 'say' and 'think' to give a tentative opinion: I should think it will take us an hour to drive to Rome.

Need

'Need' expresses necessity: You need to exercise more often. You're putting on weight.
You don't need to wear a tie if you don't want to.

Needn't have/Didn't need to

'Needn't have' is used to talk about an action that was done but was unnecessary. We needn't have rushed to the airport. The flight was delayed.
I needn't have brought an umbrella. It didn't rain.

‘Didn't need to' is used to talk about an action that wasn’t done because it was not necessary. I didn't need to call Mike. I met him in the street.

EXERCISE ONE
EXERCISE TWO 
EXERCISE THREE 

jueves, 23 de marzo de 2017

PAST PERFECT.



Using the Past Perfect 

by www.perfect-english-grammar.com


Past Perfect Infographic 
 
 
1: A finished action before a second point in the past.
  • When we arrived, the film had started (= first the film started, then we arrived).
We usually use the past perfect to make it clear which action happened first. Maybe we are already talking about something in the past and we want to mention something else that is further back in time. This is often used to explain or give a reason for something in the past.
  • I'd eaten dinner so I wasn't hungry.
  • It had snowed in the night, so the bus didn't arrive.
If it's clear which action happened first (if we use the words 'before' or 'after', for example), the past perfect is optional.
  • The film started before we arrived / the film had started before we arrived.
2: Something that started in the past and continued up to another action or time in the past. The past perfect tells us 'how long', just like the present perfect, but this time the action continues up to a point in the past rather than the present. Usually we use 'for + time'. We can also use the past perfect continuous here, so we most often use the past perfect simple with stative verbs.
  • When he graduated, he had been in London for six years. (= He arrived in London six years before he graduated and lived there until he graduated, or even longer.)
  • On the 20th of July, I'd worked here for three months.
3: To talk about unreal or imaginary things in the past. In the same way that we use the past simple to talk about unreal or imaginary things in the present, we use the past perfect (one step back in time) to talk about unreal things in the past. This is common in the 3rd conditional and after ´WISH´.
  • If I had known you were ill, I would have visited you.
  • She would have passed the exam if she had studied harder.
  • I wish I hadn't gone to bed so late!

martes, 7 de febrero de 2017

PRESENT PERFECT SIMPLE AND CONTINUOUS





Form
Present Perfect Simple
Present Perfect Progressive
irregular verbs: form of 'have' + 3rd column of irregular verbs
Example:
I / you / we / they have spoken
he / she / it has spoken
regular verbs: form of 'have' + infinitive + ed
Example:
I / you / we / they have worked
he / she / it has worked
form of 'have' + been + verb + ing
 
Example:
I / you / we / they have been speaking
he / she / it has been speaking
Exceptions
Exceptions when adding 'ed' :
  • when the final letter is e, only add d
Example:
love - loved
  • after a short, stressed vowel, the final consonant is doubled
Example:
admit - admitted
  • final l is always doubled in British English (not in American English)
Example:
travel - travelled
  • after a consonant, final y becomes i (but: not after a vowel)
Example:
worry - worried
but: play - played
Exceptions when adding 'ing' :
  • silent e is dropped. (but: does not apply for -ee)
Example: come - coming
aber: agree - agreeing
  • after a short, stressed vowel, the final consonant is doubled
Example: sit - sitting
  • after a vowel, the final consonant l is doubled in British English (but not in American English).
Example: travel - travelling
  • final ie becomes y.
Example: lie - lying
Use
Both tenses are used to express that an action began in the past and is still going on or has just finished. In many cases, both forms are correct, but there is often a difference in meaning: We use the Present Perfect Simple mainly to express that an action is completed or to emphasise the result. We use the Present Perfect Progressive to emphasise the duration or continuous course of an action.
Result or duration?
Do you want to express what has happened so far or how long an action has been going on yet?
Present Perfect Simple
Present Perfect Progressive
Result (what / how much / how often)
I have written 5 letters. / I have been to London twice.
Duration (how long)
I have been writing for an hour.
Certain verbs
The following verbs are usually only used in Present Perfect Simple (not in the progressive form).
  • state: be, have (for possession only)
Example: We have been on holiday for two weeks.
  • senses: feel, hear, see, smell, taste, touch
Example: He has touched the painting.
  • brain work: believe, know, think, understand
Example: I have known him for 3 years.
Emphasis on completion or duration?
Do you want to emphasise the completion of an action or its continuous course (how has somebody spent his time)?
Present Perfect Simple
Present Perfect Progressive
Emphasis on completion
I have done my homework. (Meaning: My homework is completed now.)
Emphasis on duration
I have been doing my homework. (Meaning: That's how I have spent my time. It does not matter whether the homework is completed now.)
Result or side effect?
Do you want to express that a completed action led to a desired result or that the action had an unwanted side effect?
Present Perfect Simple
Present Perfect Progressive
desired result
I have washed the car. (Result: The car is clean now.)
unwanted side effect
Why are you so wet? - I have been washing the car. (side effect: I became wet when I was washing the car. It does not matter whether the car is clean now.)
Time + negation: last time or beginning of an action?
In negative sentences: Do you want to express how much time has past since the last time the action took place or since the beginning of the action?
Present Perfect Simple
Present Perfect Progressive
since the last time
I haven't played that game for years. (Meaning: It's years ago that I last played that game.)
since the beginning
I haven't been playing that game for an hour, only for 10 minutes. (Meaning: It's not even an hour ago that I started to play that game.)
Permanent or temporary?
If an action is still going on and we want to express that it is a permanent situation, we would usually use the Present Perfect Simple. For temporary situations, we would prefer the Present Perfect Progressive. This is not a rule, however, only a tendency.
Present Perfect Simple
Present Perfect Progressive
permanent
James has lived in this town for 10 years. (Meaning: He is a permanent resident of this town.)
temporary
James has been living here for a year. (Meaning: This situation is only temporary. Maybe he is an exchange student and only here for one or two years.)
Signal words
Present Perfect Simple
Present Perfect Progressive
  • how often
  • ... times
  • how long
  • since
  • for
Exercises on Present Perfect Simple and Present Perfect Progressive