"The man reads the newspaper."
अनुवाद:आदमी अख़बार पढ़ता है।
They don't quite mean the same but the difference is very subtle.
आदमी अख़बार पढ़ रहा है - the man is reading the newspaper. This means that the mean is reading the newspaper right now. At this moment he is reading it. We don't know whether he regularly does it or not. Perhaps this is his first time reading one. Consider this sentence: The man never usually reads but right now he is reading the newspaper.
आदमी अख़बार पढ़ता है - the man reads the newsaper. This means that the man reads the newspaper as a habitual action, he regularly reads the newspaper, he does it over and over again. Every day the man reads the newspaper. The man reads the newspaper with his breakfast. The man reads the newspaper on the train.
Because the meanings are different Duolingo will not accept आदमी अख़बार पढ़ रहा है.
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