Subject-verb agreement: find the real subject

The item. The sentence is split into parts (a), (b) and (c). Option (d) is No error. Choose the part that contains the wrong word. In one sitting, 2019 (II), the sentence came in four parts with no 'No error' option, so one part had to be wrong. The reading method:

• Read the whole sentence once before you judge any part. Many errors show only across parts: the subject sits in (a) and its verb in (c).
• Test every part in a fixed order: subject and verb, then tense, then verb form, then articles and nouns, then pronouns, then prepositions and word choice.
• Mark the part that holds the word you would change, not the part that creates the rule.
• Choose No error only when every part has passed every check. A wrong answer costs a third of a mark, so a guess is not free.

The agreement check:

• Find the verb. If it has a helping verb (an auxiliary: is/are, was/were, has/have, does/do), the helper carries the number.
• Find its subject: ask 'who or what is doing this?'.
• Cross out the intervening phrase between them (of ..., in ..., on ..., made by ..., regarding ...). What is left is the head noun.
• Singular head noun: singular verb (is, was, has, verb + s). Plural head noun: plural verb (are, were, have, no s).

• An uncountable noun has no plural and takes a singular verb: news, information, advice, progress, furniture. 'The news is good.'
• A clause (a group of words with its own verb) or a 'to' phrase used as the subject is one idea, so it is singular, even if it contains 'and': 'To read widely and write daily is the best training.'
• All that + clause means 'everything that': singular.
• A fraction, percentage or 'part of' takes its number from the noun after 'of': 'Half of the milk has gone sour'; 'Half of the eggs were broken.'
• There is / there are: 'there' is only a filler, not the real subject. The real subject comes after the verb, and the verb agrees with it: 'There is a reason'; 'There are two reasons.'

• These are distributive words: they deal with members one by one.
• Each / every + singular noun: singular verb. 'Every room has a fan.'
• Each of / either of / neither of / every one of + plural noun: still singular. 'Neither of the answers is right.'
• Each and every: singular.
• Many a + singular noun: singular verb. 'Many a soldier has died here.'
• None: this exam treats it as 'not one' and wants a singular verb: 'None of these problems is more serious.' Everyday English often uses 'are'; on this paper, use 'is'.
• A verb in a 'that' or 'who' part after these words is singular too: 'each and every thing that is connected with drama'.

• A and B: plural verb. 'Ravi and his sister are here.'
• Either A or B / Neither A nor B / Not only A but also B: the verb agrees with B, the subject nearer to it. 'Either the teacher or the students are wrong.' 'Either the students or the teacher is wrong.'
• A as well as B / A along with B / A together with B / A with B: the verb agrees with A, the first subject. 'The captain, as well as his players, was praised.'
• Commas around a phrase are a signal: the words inside the commas are extra. The subject comes before the first comma.

• One of the + plural noun: 'one of the tallest buildings', never 'one of the tallest building'. Do not drop 'of' or 'the' either.
• The main verb agrees with 'one': 'One of my friends lives in Pune.'
• A relative clause is a group of words that starts with who, which or that and describes a noun. The noun it describes is its antecedent.
• After 'one of the + plural noun', the antecedent is the plural noun, so the verb in the relative clause is plural: 'one of the best speakers who have addressed us'.
• Exception: the only one of ... who/that takes a singular verb, because now the clause describes the one: 'the only one of the students who has passed'.