Gap-filling : - A gap-fill is a practice exercise in which learners have to replace words missing from a text. These words are chosen and removed in order to practise a specific language point.

Prepositions :  A preposition is a word or group of words used before a noun, pronoun, or noun phrase to show direction, time, place, location, spatial relationships, or to introduce an object. Some examples of prepositions are words like "in," "at," "on," "of," and "to."

Use of Some Important Prepositions :

(A) Time and Date : at, on, in, by, to, till, until, during, for, since, from, within, before, after.

Example of preposition "At" :           

• at 8 o'clock, at midnight, at night, at the beginning/end, at dawn, at sunset, at Christmas etc.

In the question : -

Change is the progress _____________ civilization. It started its journey since the dawn of civilization. Men become indulged ___________ the course of change. Men become accustomed to the changing situation. It denotes that we are gradually heading ___________ a knowledge based society.

In the first blank part , the correct preposition that can be placed in the blank part is of .

In the second blank part , the correct preposition that can be placed in the blank part is of .

In the third blank part , the correct preposition that can be placed in the blank part is towards .

Thus , the Correct Option is C , which is Of , Of , Towards  .

Gap-filling : - A gap-fill is a practice exercise in which learners have to replace words missing from a text. These words are chosen and removed in order to practise a specific language point.

Prepositions :  A preposition is a word or group of words used before a noun, pronoun, or noun phrase to show direction, time, place, location, spatial relationships, or to introduce an object. Some examples of prepositions are words like "in," "at," "on," "of," and "to."

Use of Some Important Prepositions :

(A) Time and Date : at, on, in, by, to, till, until, during, for, since, from, within, before, after.

Example of preposition "At" :           

• at 8 o'clock, at midnight, at night, at the beginning/end, at dawn, at sunset, at Christmas etc.

In the question : -

Most UFO sightings occur ______________  the night, either late in the evening or in the early hours of the morning, ____________  they take place on a dark moonless night when the person is alone on a country road.

In the first blank part , the correct modal that can be placed in the blank part is for .

In the second blank part , the correct modal that can be placed in the blank part is often .

Thus , the Correct Option is B , which is For , Often .

Gap-filling : - A gap-fill is a practice exercise in which learners have to replace words missing from a text. These words are chosen and removed in order to practise a specific language point.

Prepositions :  A preposition is a word or group of words used before a noun, pronoun, or noun phrase to show direction, time, place, location, spatial relationships, or to introduce an object. Some examples of prepositions are words like "in," "at," "on," "of," and "to."

Use of Some Important Prepositions :

(A) Time and Date : at, on, in, by, to, till, until, during, for, since, from, within, before, after.

Example of preposition "At" :           

• at 8 o'clock, at midnight, at night, at the beginning/end, at dawn, at sunset, at Christmas etc.

(b) Place : (at, in, on, to) town, address, specific place.

• at small village,        

  Example : at Mumbai , at Panipat, at 18 Ranjit Road.

In the question : -

Sadao had taken this ____________ his mind as he did everything his father said, his father who never joked or played __________ him but who  spent infinite pains ____________ him who was his only son.

In the first blank part , the correct preposition that can be placed in the blank part is into .

In the second blank part , the correct preposition that can be placed in the blank part is with .

In the third blank part , the correct preposition that can be placed in the blank part is upon .

Thus , the Correct Option is D , which is Into , With , Upon  .