The scientist asked the assistant ______ the samples before leaving the laboratory.

Answer and explanation

Correct answer: D. to label

  1. Step 1: The verb 'ask' with an object takes an infinitive. Step 2. The infinitive is 'to label'. Answer: to label. Why not the others: a gerund, a bare verb or a relative clause does not fit the pattern.

Practise more Grammar in Context (Set 2).

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