This article is about the participial use of the “verb stem + रहा” idiom.
In Hindi, continuous verbs are formed according to the following idiom:
verb stem + रहा / रही / रहे + form of होना
The verb stem provides the basic meaning of the verbal construction. The form of रहा indicates that this is a continuous verb, and agrees in gender and number with the subject of the verb. The form of होना indicates the tense and mood of the verb construction.
Etymologically, रहा is related to the verb रहना (“to remain / continue / abide / live”), and evolved as a verbal auxiliary.
Consider a few examples:
तुम क्या कर रही थी – “What were you doing?”
In this example, the addressee is female since the form of रहा is रही and the auxiliary is थी, both of which are feminine. थी is past tense, so this is a past continuous form.
तुम क्या कर रहे हो – “What are you doing?”
In this example, the addressee is masculine. Since हो is present tense, this is a present continuous verb form.
वह अभी जा रही होगी – “She must be going right now” (i.e., “I presume that she is going right now”).
In this example, a future form of होना was used (होगी), which indicates the presumptive mood.
Thus, this idiom (like all verbal idioms in Hindi) is a synthesis of aspect, tense, and mood; the form of रहा indicates the continuous aspect, the form of होना indicates tense and mood. This synthesis makes the Hindi verbal system quite elegant.
Very rarely, some Hindi speakers will employ this idiom as a participle. In other words, a speaker will delete the form of होना and use the verb stem + रहा as a verbal adjective. It must be cautioned that the participial usage is very rare, and exhibits poor style – it is not proper Hindi.
Normal Hindi usage employs imperfective participles for this purpose:
वहां भागता हुआ लड़का मेरा भाई है – “The boy running over there is my brother”
However, some people may say:
वहां भाग रहा लड़का मेरा भाई है – “The boy running over there is my brother”
In this example, the continuous verb idiom was converted into a participle. This usage is very rare, and is improper. Hindi style definitely prefers the use of imperfective participles.
See the article about imperfective participles for more information.