Correct Answer:
C. Do not let child drink this dirty water
The question requires choosing the grammatically correct English sentence. The sentences involve the use of the causative verb "let," which has a specific grammatical structure.
The correct answer is C: Do not let child drink this dirty water. The correct structure for the causative verb "let" is "let + object + base form of the verb (infinitive without 'to')." In this sentence, "child" is the object, and "drink" is the base form of the verb, making the sentence grammatically sound.
- A: Do not let child have drunk this dirty water is incorrect because "have drunk" is the present perfect form, which is not used after "let" in this construction.
- B: Do not let child to drink this dirty water is incorrect because "let" does not take "to" before the infinitive. This is a common error.
- D: Do not allow child have drunk this dirty water is incorrect. While "allow" is a causative verb, it typically takes "to + infinitive" (e.g., "Do not allow the child to drink"), and "have drunk" is still an incorrect verb form in this context.