Grammar & vocabulary formulas

A past action with a present result, or a period that runs up to now. Never with a finished past time (yesterday, ago, last year, in 2019).

An action that began in the past and is still going on: 'She has been teaching here since June' / 'for three months'. It is also used for an activity that has only just stopped, leaving a visible result: 'The roads are wet; it has been raining.' Use since or for here, not from.

Marks an action completed before another past action or a stated past time: 'The train had left when we reached the platform.' Not for a lone past event: 'I went there yesterday', not 'I had gone there yesterday'.

An action that will be complete before a stated future point: 'By March, the team will have tested every unit.'

These clauses (also before, after, once) take the present simple, or the present perfect for an action that will be complete, even for future time; 'will' goes only in the main clause: 'I will call you when I reach the station', not 'when I will reach the station'; 'You may leave once you have signed the register.' The rule covers clauses of time and condition only. A when- or if-clause that is the object of a verb such as know, ask, tell or wonder is a noun clause and takes 'will' as usual: 'Nobody knows when the results will be declared.' 'If you will' is also correct where 'will' means willingness, as in a polite request: 'If you will wait here, I will fetch the form.'

A general truth or a rule that always holds: 'If you mix blue and yellow paint, you get green.'

A real, possible future: 'If the supply fails, the backup will start.'

An unreal present or an unlikely future. Formal English uses 'were' for every person: 'If I were the organiser, I would start earlier.'

An unreal past. 'Would have' never goes in the if-clause. Inverted form without 'if': 'Had I known, I would have helped.' A mixed conditional joins an unreal past condition to a present result: 'If I had taken that job, I would be living in Pune now.'

'She said that she was tired.' In reported speech after a past reporting verb, each tense moves one step back: is → was, is doing → was doing, has done → had done, did → had done (often left as did when the order of events is clear), will → would, can → could, may → might. A universal truth keeps the present: 'The teacher said that light travels faster than sound.' After a present or future reporting verb nothing shifts: 'She says that she is tired.'

Only transitive verbs have a passive. Happen, occur, arrive, die, seem and other intransitive verbs cannot be made passive: 'The accident happened', never 'was happened'. Not every transitive verb has one either: have (in the sense of own), resemble, lack and suit are not normally passive ('Ravi resembles his father', never 'His father is resembled by Ravi').

Also for plain 'X or Y'. The verb agrees with the nearer subject: 'Neither the lecturer nor the students were informed.' 'Either the students or the lecturer is responsible.'

Also 'in addition to', 'accompanied by', 'like', 'including'. 'The captain, along with his players, was felicitated.' Of the joining words, only 'and' makes a plural subject, and even 'and' does not when the two nouns name one person or one idea (see the list below).

'One of the valves is faulty.' But in 'one of the + plural noun + who/that + verb', the relative clause refers to the plural noun, so its verb is plural: 'She is one of the engineers who have designed the dam.' With 'the only one of ... who', it is singular again.

'The number of applicants has doubled.' 'A number of applicants have complained.'

'Each of / Either of / Neither of + plural noun' is also singular in formal English: 'Neither of the answers is correct.' Exception: 'each' AFTER a plural subject keeps the verb plural: 'The boys each have a locker.'

Articles, possessives and numbers come first. 'a beautiful old Kashmiri woollen shawl' (opinion, age, origin, material); 'a large round wooden table' (size, shape, material).

These take 'to', never 'than', and never 'more' in front ('more superior' and 'more preferable' are wrong): 'She is senior to me by two years.' Likewise the verb 'prefer X to Y': 'He prefers trains to buses.' With infinitives, use 'rather than': 'He prefers to walk rather than wait.'

Each half stands directly before matching words: noun with noun, verb with verb. 'She is not only a singer but also a dancer.' 'He not only designs circuits but also tests them.' Also whether ... or, neither ... nor.

Inverted order after the negative opener. 'No sooner had the lecture begun than the lights went out.' 'Hardly had we sat down when the bell rang.' 'Before' may replace 'when' after hardly and scarcely, and the past simple form 'No sooner did + subject + V1 ... than' is also correct: 'No sooner did the lecture begin than the lights went out.' Never 'No sooner ... when' or 'Hardly ... than'.