'I saw him going to market.'' (Make it compound)

• The correct compound sentence is: I saw him and he was going to market.
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• Compound sentence এ দুই বা ততোধিক principal clause বা co-ordinate clause থাকে।
এছাড়া Compound sentence এ সাধারণত and, or, but, yet, so, therefore, otherwise, else, both --- and, either --- or, neither — nor, not only --- but also ইত্যাদি co-ordinating conjunction দ্বারা দুইটি principal clause যুক্ত থাকে।

অপশনে উল্লেখিত sentence গুলোর মধ্যে কেবল - I saw him and he was going to market -বাক্যটিতে দুইটি clause রয়েছে এবং and দ্বারা যুক্ত হয়েছে।
তাই সঠিক compound sentence - I saw him and he was going to market. 

Source: A Passage to the English Language by S. M. Zakir Hussain.