Fill in the blank with the correct option :
No sooner did I step outside _____ it started raining.

Question

Accepted Answer

The correct answer is Option 2: than

Explanation:

The phrase "no sooner...than" is a correlative conjunction used to indicate that one event happens immediately after another. It establishes a specific relationship of sequence and immediacy.

*   **Why Option 2 (than) is correct:** The grammatical structure "no sooner...than" is a fixed idiom. "Than" is the only word that correctly completes this idiom, creating a grammatically sound and meaningful sentence. The sentence "No sooner did I step outside than it started raining" means that the rain began almost immediately after I stepped outside.

*   **Why Option 1 (then) is incorrect:** While "then" can indicate sequence, it doesn't fit the specific correlative structure of "no sooner." Using "then" would make the sentence grammatically incorrect and disrupt the intended meaning of immediate succession.

*   **Why Option 3 (when) is incorrect:** "When" introduces a time clause, but it doesn't work with "no sooner" to express the immediate sequence of events. "No sooner...when" is not a standard or grammatically correct construction.

*   **Why Option 4 (only) is incorrect:** "Only" doesn't establish any temporal relationship between the two clauses. It doesn't fit the grammatical structure or the intended meaning of the sentence. It would make the sentence nonsensical.