Su: Moon is biger then humen
Correct: The moon is bigger than human.
Explanation: The definite article "the" is used especially before a noun or nouns like people or things.

Su: Astronaut can walk on the Moon
Correct:An astronaut can walk on the Moon.
Explanation: The indefinite article "an" is used before an initial vowel sound.

Su: It is ease to walk ,but it is hard to run.
Correct: It is easy to walk ,but it is hard to run.

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Thank you for submitting your homework, Su! You did a great job. See you tomorrow.

-Teacher Isabel