Ethics is my favorite subject. Ethics is not complex, but it¡¯s informative and ______.
My favorite teacher is my technical arts teacher, Mrs. Gwon. She is diligent but strict.
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Are the passage grammatical? What will be suitable for the blank in the passage?
interesting?
Yes, the grammar is good here. You do need a comma before "but".
The passage is grammatically correct.
As for the blank in the passage, it seems that a word is missing after "informative and." Without additional information, it is difficult to provide a specific answer. However, here are a few suggestions for words that could potentially fill the blank and complete the sentence: engaging, thought-provoking, enlightening, rewarding, important, or enlightening. The choice would depend on the writer's intended meaning and the context of the sentence.