Over long periods of time, layers of sediments builds up to a height of a few kilometers.
- (a)Over long periods of time,
- (b)layers of sediments builds up
- (c)to a height of a few kilometers.
- (d)No Error
Correct — B, 'layers of sediments builds up.' The head of the subject is the plural noun 'layers', which needs the plural verb 'build up'. The words 'of sediments' form an intervening phrase and do not change the number of the subject, so the singular 'builds up' breaks agreement — 'layers … build up' is required.
- (a)Over long periods of time, — Error-free — a correctly formed adverbial phrase of time with no grammatical fault.
- (c)to a height of a few kilometers. — Error-free — 'to a height of a few kilometers' is idiomatic and correctly formed.
- (d)No Error — There is an error — the plural subject 'layers' does not agree with the singular verb 'builds up' — so 'No Error' is not the answer.
This is an error-spotting item on subject-verb agreement — the plural head noun 'layers' takes a plural verb ('build up'), and the intervening phrase 'of sediments' must be ignored when fixing the verb.
No directly related past PYQ was found.
- practice — not a real PYQ
Spot the error: (a) A bunch of keys / (b) were lying / (c) on the table. / (d) No error
- (a)A bunch of keys
- (b)were lying
- (c)on the table.
- (d)No error
Answer(b) were lying — the head noun 'a bunch' is singular, so it needs 'was lying', not 'were'.
- practice — not a real PYQ
Choose the correct option: The stack of papers ___ on the desk.
- (a)are
- (b)were
- (c)is
- (d)have
Answer(c) is — the singular head noun 'stack' governs the verb, not the plural 'papers'.