को ko is the second case/kaaraak and this ko is added to the receiver of the verb.
In English: Verb + noun/pronoun
In Hindi: Noun/pronoun + ko + verb
Call Ram – राम को बुलाओ – Ram ko bulavo
Eat the apple – सेब को खाएं – Seb ko khaayen
Clean the table – मेज़ को साफ करें – Mej ko saaf karen
Teach her – उसे सिखाओ – Use sikhaavo [Here ko is merged with the pronoun (Lesson 16)]
To decide whether to add ko or not, ask who / what receives the verb.
If the receiver is who (living) – add ko
If the receiver is what (non-living) – need not add ko
Call Ram – Call whom / what?
Call Ram – Ram is living/human being, so ko must be added to Ram.
राम को बुलाओ – Ram ko bulavo
Eat the apple – Eat whom / what? – Apple is non-living and so ko need not be added to apple.
Eat the apple
सेब खाएं – Seb khaayen
Few examples:
Clean the table – मेज़ साफ करें – Mej saaf karen
Teach her – उसे/उसको सिखाओ – Use/usko sikhaavo
Finish the work – काम खत्म करो – Kaam khatm karo
Keep the book away – पुस्तक दूर रखें – Pustak door rakhen
Bring money – पैसे लाएं – Paise laayen
Ram killed Ravan – राम ने रावण को मारा – Ram ne ravan ko maara
1. In the subject + को ko + complement + verb constructions, the verbs express the state of mind, physical experience, involuntarily actions, feelings, obligations, and emotions.
Ram has fever
राम को बुखार है – Ram ko bukhaar hai
Rani laughed
रानी को हँसी आयी – Rani ko hansi aayi [This literally translates to “laughter came to Rani”]
2. Whenever the objects are followed by the dative postposition को ko, the verb remains in the masculine singular form.
राम ने बहिन / बहिनों को बुलाया
Ram ne bahin / bahinon ko bulaaya
Ram called (his) sister / sisters
हमने लड़के लड़को लड़की लड़कियों को पढ़ाया
Humne ladke / ladko / ladkee / ladkiyon ko padaaya
We taught the boy / boys / girl / girls
3. When the sentence has both direct and indirect objects, add ko to indirect object only.
The woman gives the child to the girl
महिला लड़की को बच्चा देती है
Mahila ladakee ko bachcha detee hai
I will give this ice cream to you
मैं तुम्हें / तुमको यह आइसक्रीम दूंगा
Main tumhen / tumko yah aaisakreem doonga
The general structure of a Hindi sentence is: Subject + indirect object + direct object + verb
4. The postposition ko is added to the subject noun/pronoun if it is followed by an object and the verb chaahiye ‘want’ or the modal ‘should’ [The lesson on want and should will come later].
(i.e., subject + ko + object + chaahiye).
He wants this newspaper
उसे यह अखबार चाहिए
Use yah akhabaar chaahiye
He should do this work
उसे यह काम करना चाहिए
Use yah kaam karana chaahiye
5. को ko is also used for the word “to”.
Give these books to Rashmi
रश्मि को ये किताबें दे दो
Rashmi ko ye kitaaben de do
I will give this ice cream to you
मैं तुम्हें / तुमको यह आइसक्रीम दूंगा
Main tumhen / tumko yah aaisakreem doonga
6. Ko and mein are used with nouns denoting time.
He came at night
वह रात को आया – Vah raat ko aaya
He came during the night
वह रात में आया – Vah raat mein aaya
7. Ko is not added to place nouns.
I am going to Mumbai
मैं मुंबई जा रहा हूँ – Main Mumbai ja raha hoon
She is coming to my home
वह मेरे घर आ रही है – Vah mere ghar aa rahee hai
8. Ko is added to the days of the week and dates.
The school starts on March 31st
स्कूल 31 मार्च को शुरू होगा – Skool 31 maarch ko shuroo hoga
My parents will arrive on Sunday
मेरे माता-पिता रविवार को आएंगे – Mere maata-pita ravivaar ko aaenge
9. Ko is used to emphasize the inanimate object.
Read the book
किताब पढ़ें – Kitaab paden
किताब को पढ़ें – Kitaab ko paden