1. You should divide your class into three groups, and by using the following expressions, investigate your classmates' plans for this weekend, this Chuseok, and this winter vacation.

2.Summarize the result in brief as follows.

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Are the directions above grammatical? Would you check them?

Excellent!

Sra

To check if the directions above are grammatically correct, we can break down the sentences and analyze them one by one.

1. "You should divide your class into three groups, and by using the following expressions, investigate your classmates' plans for this weekend, this Chuseok, and this winter vacation."

This sentence is grammatically correct. It suggests dividing the class into three groups and using specific expressions to inquire about classmates' plans for three different periods: this weekend, this Chuseok (Korean holiday), and this winter vacation.

2. "Summarize the result in brief as follows."

This sentence is also grammatically correct. It instructs you to summarize the result concisely using the following format.

Based on the analysis, both sentences appear to be grammatically correct.