Question

Fill in the blank with the most appropriate word:
The old lady thanked me _______ helping her across the street.
a)with
b)on
c)about
d)for

Answer 1

Hint: A preposition is used before a noun or verb. It is a joining word between two sentences.

Complete step-by-step answer:

 People thank others for something. Therefore, the old lady thanked me for helping her across the street. Thus, the correct answer is d.
Option a is wrong because ‘The old lady thanked me with helping her across the street’ is wrong. It does not make any sense in this sentence. ‘Thanking someone with something’ would imply that a person is giving someone something as a gesture of thanking him. For example, Rahul thanked Shekhar for getting him an internship, with a new video game. This means that Rahul gifted Shekhar a new video game as a gesture of thanking Shekhar for helping him get an internship. Since that is not the meaning implied in the given sentence, option a is wrong.
Option b is ‘on’ and it is a wrong preposition to be used in this sentence. ‘The old lady thanking me on helping her across the street’ means the old lady did not thank me until she crossed the street. Thus, it is not ‘the most appropriate word’ to be used.
Option c, that is ‘about’, means the old lady thanked me about helping her across the street implies that I met the old lady on a day other than the day I helped her across the street and she was thanking me about it by recalling it. Since that is not the case here, option c is a wrong answer.

Note: After using a preposition in a sentence, it is advised to re-read the whole sentence to see if the preposition used is befitting the sentence. Sometimes a particular phrase may be grammatically correct such as ‘thanking on doing something’ but it is not appropriate in this sentence. The key lies in using ‘the most appropriate word’.