Understanding the TOEFL Grammar Item: Inverted Sentence Structures in Negative Adverbial Clauses

The given sentence is:

"Not until the 20th century _____ in most parts of the world."

Answer choices:

1. women could vote
2. could women vote
3. women were voting
4. they could vote

To determine the correct answer, we need to analyze sentence structure, verb placement, and common misunderstandings related to negative adverbial clauses.

1. Identifying the Grammar Rule: Inversion in Negative Adverbial Clauses

This sentence begins with "Not until the 20th century", which is a negative adverbial phrase. In English, when a negative or restrictive phrase (such as not until, never, hardly, rarely, not only, little, scarcely) appears at the beginning of a sentence, subject-verb inversion is required.

Normally, the sentence in standard subject-verb-object (SVO) word order would be:

👉 Women could not vote in most parts of the world until the 20th century.

However, because the sentence begins with "Not until the 20th century", inversion is triggered. The correct structure would be:

👉 Not until the 20th century could women vote in most parts of the world.

Thus, the correct answer is:

✅ (B) could women vote.

2. Explanation of Why Other Choices Are Incorrect