Modal Verbs

- They form the negative adding not to the modal verb.
- They form the interrogative without the auxiliary verb (They are their own auxiliary).
- They don't add -s/-es of third person.
- They are followed by infinitive without TO.

TYPES:

• ADVICE: Should, ought to, had better, be supposed to.

- For logic and advice or instructions: Should, ought to (they have the same meaning).
- To say the best option in a situation (stronger than the previous): Had better.
- To say the correct way of doing something: be supposed to.

• PERMISSION: Can, could, may, be allowed to.

- Asking for permission: can, could, may (very formal).
- Giving permission: can, may (not usually).          Note: couldn't is not used.
- About rules: Be allowed to.

• OBLIGATION: Must, have to, don't have to, needn't.

- Obligation by the person who speaks: must.
- When you oblige yourself: have to.               Note: both "must" and "have to" use HAD TO in past.
- Lack of obligation: don't have to, needn't.

• PROHIBITION: Mustn't.

• NECESSITY: Need to, didn't need to, didn't have to.

- Possitive form: Need to.
- Negative form: Didn't need to, didn't have to.

• ABILITY: Can, could, be able to.

- Present: Can.
- Past: Could.
- Other tenses: Be able to.

• POSSIBILITY/PROBABILITY: Must, may, might, could, can't, couldn't.

- 100% sure: must.        Note: past tense form is "must+have+Vparticiple" & "mustn't is not used.

- 50% sure, possible: may, might, could.     Note: past tense form is "modal+have+Vparticiple".

COULDN'T = IMPOSSIBLE                    MAY NOT/MIGHT NOT = POSSIBLE

- 100% impossible: can't, couldn't.     Note: past tense form is "can't/couldn't+have+Vparticiple".


Links to exercises:
Modal Verbs Advice
Modal Verbs Permission
Modal Verbs Ability
Modal Verbs Obligation
Modal Verbs Probability 1
Modal Verbs Probability 2
Modal Verbs Necessity
Modal Verbs Mix 1
Modal Verbs Mix 2
Modal Verbs Text Quiz
Modal Verbs Final Test

Infinitives Vs Gerund

GERUNDS
We use gerunds (verb+ ing):
- After prepositions
- As the subject or object of a sentence
- After certain verbs: enjoy, fancy, discuss, dislike, finish, mind, suggest, recommend, keep, avoid, miss, appreciate, delay, postpone, practise, consider, can't stand, can't help, risk, admit, deny, mention, imagine, tolerate, understand, involve, complete, report, anticipate, recall.

TO + INFINITIVE
We use to + infinitive:
- After many adjectives.
- To show purpose
- After certain verbs: agree, ask*, decide, help*, plan, hope, learn, want*, would like*, promise, can afford, manage, prepare*, demand, choose, offer, wait, would hate*, would love*, seem, expect*, intend, pretend, refuse, tend, would prefer*, deserve, appear, arrange, claim.

*We can use an object before the infinitive with these verbs.

BARE INFINITIVE 
We use bare infinitive (without TO):
- After modal verbs
- After "let" and "make" and sometimes "help"
- After some verbs of perception (see, watch, hear, feel, sense)
- After expressions with "why"

Video

Links to exercises:
Infinitive Vs Gerund 1
Infinitive Vs Gerund 2
Infinitive Vs Gerund 3

Reported Speech

USES:
The reported speech is used when someone says a sentence and we want to tell someone else what the first person said before.

• If the sentence starts in present there is no backshift of tense: She says she works in an office.
• If the sentence starts in past there is backshift of tense: She said she worked in an office.

NOTE: Backshift of tense is not necessary when the sentence is still true (compare the previous examples).

REPORTING QUESTIONS:

• Wh- Questions: Keep the question word + grammar change into a normal sentence.

"Where do you live?"     -     She asked me where I lived

• Yes/No Questions: IF + grammar change into a normal sentence.

"Do you like chocolate?"     -     She asked me if I liked chocolate.

REPORTING REQUESTS:  Ask me + TO + INF

"Close the window, please"     -     She asked me to close the window.

REPORTING ORDERS:  Tell me + TO + INF

"Sit down!"     -     She told me to sit down.

ADDITIONAL CHANGES:

It is necessary to have the expressions of time changed and also the pronouns and possesives.

This - That                                                   Ago - Before

Today - That day                                         Last - The previous

These - Those                                              Here - There

Now - Then                                                 Tomorrow - The following day / The next day

Video

Links to exercises:
Reported Speech mix 1 (Easy)
Reported Speech mix 2 (Medium)
Reported Speech mix 3 (High)
Reported Speech mix 4 (Questions)
Reported Speech - Requests and orders

Statives Verbs

Some verbs are only used in simple tenses (not continuous tenses). These verbs are called stative or state verbs. They are verbs about liking or disliking something, mental states... but not actions. The verbs which show action are called dynamic.

Some verbs have both functions:

• BE: Is usually a stative verb but it can be used to show behaviour or acts. 

You are stupid (as a part of your personality)    -    You are being stupid (only now, not usually)

• HAVE: Used as a stative verb means own. Used as a dynamic verb is part of an expression.

I have a car (I own it)          -         I am having a great time (To spend time in a funny way)

• SEE: As a stative verb, see means with your eyes, understand. As a dynamic verb it means meet or have a relationship.

I see what you mean / It's dark. I can't see anything.      -      I'm seeing Rob tomorrow.

• THINK: It can mean opinion as a stative verb or consider as a dynamic verb.

I think the coffee is great.          -          I'm thinking about my next holiday destination. 

• TASTE: It can mean certain taste as a stative verb or the action of tasting as a dynamic verb. (It happens the same with smell, feel and look.)

This soup tastes delicious.          -          The chef is tasting the soup.

Here you have a list with the stative verbs and examples.

Video

Links to exercises:
Stative Verbs 1
Stative or Dynamic 1
Stative or Dynamic 2
Stative or Dynamic 3
Both Meanings