Questions & Answers about पिता मेज़ से पत्र ले रहे हैं।
Because ले रहे हैं is a progressive/imperfective verb form, not a perfective one.
In Hindi, the postposition ने is typically used with the subject of a transitive verb in the perfective aspect, for example:
- पिता ने पत्र लिया। = Father took the letter.
But in the sentence:
- पिता मेज़ से पत्र ले रहे हैं।
the verb means are taking, which is ongoing, so ने is not used.
A useful contrast:
- पिता पत्र लेते हैं। = Father takes letters / Father takes the letter(s).
- पिता पत्र ले रहे हैं। = Father is taking the letter.
- पिता ने पत्र लिया। = Father took the letter.