Given a sentence, return the position of the 2nd highest frequency word in the sentence. The position should start from 1.
This is a random sentence.
The 2nd highest frequency word in the sentence "This is a random sentence." is "a", which appears in the 3rd position.
Complete the following task based on the instruction and optional input provided.### Instruction:
Given a sentence, return the position of the 2nd highest frequency word in the sentence. The position should start from 1.

### Input:
This is a random sentence.

### Output:
The 2nd highest frequency word in the sentence "This is a random sentence." is "a", which appears in the 3rd position.