The question presented is about choosing the correct idiomatically preferred words to fill in the blanks of a given sentence. The sentence provided is:
"I don't know _____ I am ready to take the test now and _____ I will ever be ready in the future."
We need to fill the blanks with the appropriate words from the given options. Let's analyze the choices:
- Option 1: if, if
- The word if is generally used in conditional sentences, not suitable for situations where there are two possibilities.
- Using if, if here lacks clarity on the contemplation of possibilities in both blanks.
- Option 2: whether, whether
- While whether expresses uncertainty and provides the sense of contemplating possibilities, using whether in both blanks is acceptable. However, the given correct answer is "whether, if", which indicates the distinct modification at the second blank, making whether, whether not the preferred choice in this context according to the problem statement.
- Option 3: if, whether
- This combination places if in the first blank, which doesn't optimally reflect considering options. Additionally, placing whether in the second blank disrupts the sequential flow of the sentence proper to the solution's preferred choice.
- Option 4: whether, if (Correct Answer)
- The word whether is used when discussing possibilities and is ideal for the first blank: "I don't know whether I am ready".
- The conjunction if is grammatically viable in the structure for the second part of the sentence: "and if I will ever be ready in the future", providing a contrast or condition indirectly.
Therefore, the idiomatically and grammatically correct fill for the blanks is "whether, if", providing clarity and maintaining the sentence structure.