A sentence, or part of the sentence, is underlined in the actual question. Four alternatives are given for the underlined part which may improve the sentence. Choose the correct alternative and click the button corresponding to it. In case no improvement is needed, click the button corresponding to "No improvement". The sentence is: "His wife is as tall if not, taller than him."

Introduction / Context:
This is a sentence improvement question testing your understanding of comparison structures in English. The sentence compares the height of "his wife" with "him". The original structure "His wife is as tall if not, taller than him" is awkward and grammatically incomplete. You must choose the option that correctly and smoothly completes the comparison while maintaining the intended meaning.

Given Data / Assumptions:

The intended meaning is that his wife is at least as tall as he is, and possibly even taller.
The phrase should use the standard comparative pattern as tall as ... if not taller than ....
The underlined portion in the original is "as tall if not," which is incomplete because it omits as after tall.

We must avoid double comparatives such as more taller and incorrect word orders.

Concept / Approach:
In English, when we say that one person is at least as tall as another and perhaps taller, we often use the pattern: X is as tall as Y, if not taller (than Y). The as ... as construction must be complete: as tall as, not just as tall. Any option that fails to include the second as after tall or that adds unnecessary words like more taller is ungrammatical. Therefore, the best improvement will insert as after tall and position the phrase if not correctly within the comparison.

Step-by-Step Solution:
Step 1: Identify the standard comparison structure: as tall as + person, if not taller than + person. Step 2: Notice that the original underlined phrase "as tall if not," is missing the second as, so it should be "as tall as, if not". Step 3: Examine option A: as tall as, if not. This directly supplies the missing as and fits the pattern. Step 4: Option B: as taller if not is wrong because it breaks the as ... as pattern and uses taller wrongly after as. Step 5: Option C: not as tall but as is incomplete and confusing; it does not express the idea of being possibly taller. Step 6: Option E: as tall as if not more taller is ungrammatical because more taller is a double comparative and should not be used.

Verification / Alternative check:
Construct the corrected sentence with option A: His wife is as tall as, if not taller than, him. This sounds natural and clearly communicates that she is at least equal in height and maybe taller. If we try option B, His wife is as taller if not ... the structure collapses and sounds wrong to a native speaker. Option E with more taller is clearly incorrect because standard English does not combine more and the -er ending. Comparing these versions confirms that inserting "as tall as, if not" is the only acceptable improvement.

Why Other Options Are Wrong:
Option B breaks the as ... as pattern and uses taller incorrectly, making the sentence ungrammatical.
Option C changes the logic and fails to express that she may be taller; it also leaves the sentence sounding incomplete.
Option D No improvement is incorrect because the original wording is missing as and is stylistically awkward.
Option E introduces the incorrect double comparative "more taller", which is not acceptable in standard English grammar.

Common Pitfalls:
Many learners struggle with comparison structures and may overlook small words like as. They also sometimes create double comparatives such as more better or more taller, which are always wrong in formal English. When you see as + adjective, check carefully whether a second as is needed. In patterns like as tall as, if not taller, remember that the first part uses the as ... as structure and the second part switches to the simple comparative without repeating as.

Final Answer:
The correct improvement of the underlined part is "as tall as, if not", giving the sentence: His wife is as tall as, if not taller than, him.