Theory:

     I looked all over, but I could not find him.
 
     I went near the edge of the water, and I saw a black something struggling above its surface. Then it rose higher and it was the trunk of my elephant. I thought he was drowning. I was helpless because I could not jump into the water and save the four hundred pounds of him since he was much higher than I. But I saw his back rise above the water and the moment he caught my eye, he began to trumpet and struggle up to the shore. Then, still trumpeting, he pushed me into the water and, as I fell into the stream, I saw a boy lying flat on the bottom of the river. He had not altogether touched bottom but was somewhat afloat. I came to the surface of the water to take my breath and there Kari was standing, his feet planted in the sand bank and his trunk stretched out like a hand waiting for mine. I dived down again and pulled the body of the drowning boy to the surface but, not being a good swimmer, I could not swim ashore and the slow current was already dragging me down.
Explanation:
 
The narrator looked all around, but he could not find Kari anywhere.
 
He went near the edge of the water and saw something black above its surface. Finally, he realised that it was the trunk of his beloved elephant, Kari. He thought that Kari was drowning. The narrator was helpless because the elephant was too big for him. Kari weighs four hundred pounds and even higher than him. At last, the narrator saw Kari's back was lifting. When he saw the narrator, Kari began to trumpet and struggled up to the shore.
 
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The narrator saw something black above its surface
 
Kari pushed him into the stream. The narrator saw a boy lying on the bottom of the river. He dived and pulled the body of the drowning boy to the surface. However, the narrator was not a good swimmer. So he could not come ashore. The current flow of water began to drag him down.
 
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Boy drowning to the surface
 
Meanings of the difficult words:
 
S.No
 Words
Meanings
1
DrowningTo die from inhaling water into the lungs and being unable to breathe
2
Trumpet Sound of an elephant
3
Struggling Facing difficulties
Reference:
National Council of Educational Research and Training (2007). Bringing up Kari- Dhan Gopal Mukherji(7-14). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.