Directions: In the following question, some parts of the sentence may have an error. The error, if any, will be in one part of the sentence. Find out which part of the sentence has an error and select the appropriate option. If a sentence is free from errors, select 'No error' as your answer.

They coin money in (A)/ honest and accurate measures (B)/ and allow this money trade (C)/ freely on open markets. (D)/ No error (E)/.

The correct answer is 'C' i.e. this part of the sentence has an error.

Key Points

• In the given sentence, the use of the zero infinitive or base form of the verb 'trade' in part C is incorrect.
• The zero (or bare) infinitive is used after verbs of perception (see, feel, hear), many auxiliary verbs (may, should, must), the verbs make and let, and the expressions had better and would rather.
• The given sentence is talking about the purpose of coining money in honest and accurate measures i.e. to trade freely on open markets. 
• The to-infinitive is used in many sentence constructions, often expressing the purpose of something or someone's opinion about something.
• Therefore, the to-infinitive ''to trade'' should be used in place of the zero or bare infinitive 'trade'.
   

Hence, the correct answer is option 3.

Correct sentence: They coin money in honest and accurate measures and allow this money to trade freely on open markets.