What are your favorite books? 

My favorite book is cartoon book. --> ​My favorite book is a cartoon book. ​ => Corrected : The sentence is corrected grammatically.

Toto's nack is shorter than Popo's --> Toto's neck is shorter than Pupu's.  => Corrected spelling.

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Rara's ears are longer than Coco's. (Punctuation) 

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let's  play relay.How do you think? --> Let's have a race. What do you think? => Corrected : The sentence is corrected grammatically.  (Capitalization)

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