Grammar Guide

1: Past
1. Simple past (SP) "I did"
2. Past continuous/progressive (PC) "I was doing"
3. Past perfect (PP) "I had done"
4. Past perfect progressive (PPP) "I had been doing"
5. Used to "I used to"

1. SP: Used to pinpoint a certain action at a specified time in the past. Every other past tense is related to this point except 'used to.' No other past tense is used without mentioning or alluding to SP.
I ate (SP) breakfast at 8am.
2. PC: Describes the situation or simultaneous action being performed when SP occurred.
I was watching (PC) TV when the phone rang (SP).
3. PP: Expresses an action completed before SP. Used to describe the background or events leading up to a major event.
I felt (SP) sick because I had consumed (PP) too much alcohol.
4. PPP: A prolonged action that may have continued up until, but not at the same time nor past SP.
I had been searching (PPP) for hours before I finally found (SP) it.
5. Used to: Explains a past habitual action.
I used to visit my Grandma's house every summer.
I was driving (PC) home when I heard (SP) that the King had been assassinated (PP). Rebels had been threatening (PPP) him for some time.
2: Present
1. Simple present (Pr) "I do"
2. Present continuous/progressive (PrC) "I am doing"
3. Present perfect (PrP) "I have done"
4. Present perfect progressive (PrPP) "I have been doing"

1. Pr: A habitual action. Often combined with adverbs. Also used to demonstrate permanency, whereas PrC is used to demonstrate a short-term situation. "I work at the embassy" would suggest a regular position, where "I am working at the embassy" may signify it is a temporary transfer
I often play tennis.
I sing quite well.
2. PrC: A current action. Occasionally used for future tense.
Ask me later, I'm reading the newspaper (now).
3. PrP: An action completed at an unspecified time until now. Commonly combined with the words 'still' and 'yet' with negative and positive statements respectively. Often used to explain experience, albeit usually with the inclusion of the words 'ever' and 'never'. Common questions forms include "how many/ how far have you?"
Have you had breakfast yet?
I have never been to India.
4. PrPP: Used when you wish to express the amount of time you have been performing an action that started in the past and is continuing. Common question forms include "How long have you"
I have been living in Japan for five years..
3: Future
1. Simple Future (SF)
Will do "I will do"
Going to do "I am going to do"
Doing (+future time) "I am doing it tonight"
2. Future continuous/progressive (FC) "I will be doing it tonight"
3. Future perfect (FP) "I will have done it tonight"

1. There are 3 major ways to discuss simple future (SF):
l Will: We use this when we decide a future action, in invitations, or events that we have no control over such as weather.
Q: Will you come to my party?
A: Sure, I'll come.
l Going to: This is used for plans that have been decided before the current conversation.
I'm going to have a party. Will you come?
l Doing (+future time): This expresses plans that have already been arranged.
Q: Will you come to my party?
A: I'm sorry. I'm going away this weekend.
2. FC: Used to express an action that starts before but continues until a certain point in the future.
I will be working in China next summer.
3. FP: Expresses an action that has not yet happened, but will have happened by a certain future point.
I will have finished my exams by the end of the month.
We are getting married in 2005. (SF) We will be living (FC) in a house in the city, which we will have paid off (FP) by then.

Tricky points
1: Past
Active: His boss fired him.
Passive: He was fired. (by his boss)
Passive voice is use when:
1. We do not know the agent
2. We do not consider the agent important.
The object becomes the subject, and the past participle form of the verb is used in a similar manner to an adjective.
Examples:
A girl was kidnapped, but has been located.
My wallet has been stolen!
I am going to be promoted.
2: Conditionals
1. If you do, I will (If+Pr+will)
2. If you did, I would...(If+SP+would/could etc)
3. If you had done, I would have(If+PP+would/could etc+PrP)

1. This is used for discussing realistic situations, advice, threats etc.
If you are late once more, I will fire you.
2. Used for discussing hypothetical situations, dreams, wishes etc.
If I won the lottery, I would travel around the world.
3. Used for discussing hypothetical changes to the past, regrets etc.
If I had studied harder at school, I could have been a doctor.
3: Speculation(this explanation is using past tense only as an example)
1. Did (Fact-not speculation)
2. Must have done (Speaker believes it to be true)
3. Could have done (Speaker is unsure of whether it is true or false)
4. May/might have done (Speaker believes it to be false, but acknowledges possibility)
5. Might even have done (Very low possibility)
6. Couldn't have done (Speaker believes it to be impossible, but has doubts)
7. Didn't (Fact-not speculation)

1. Possibly (Less than 50% chance of being fact)
2. Probably (More than 50% chance of being fact)