Punctuation
13.
it is they who have done this noble work they have been working for a long time at last they could do the work other people also helped them
Answer: It is they who have done this noble work. They have been working for a long time. At last, they could do the work. Other people also helped them.
14.
mother is cooking now she remains always busy with cooking she cooks well everybody praises her as a good cook
Answer: Mother is cooking now. She remains always busy with cooking. She cooks well. Everybody praises her as a good cook.
15.
the rich are not always happy on the other hand the poor are not always unhappy we should not hate the poor a poor man may be an honest man but a rich man may be a dishonest man
Answer: The rich are not always happy. On the other hand, the poor are not always unhappy. We should not hate the poor. A poor man may be an honest man but a rich man may be a dishonest man.
মো. জসিম উদ্দীন বিশ্বাস, প্রভাষক, ঢাকা রেসিডেনসিয়াল মডেল কলেজ, ঢাকা