Let's go through each sentence one by one:

1. "Tung Duong ________ to school today because it is Sunday."

The correct answer is C. "doesn't go." The sentence should be: "Tung Duong doesn't go to school today because it is Sunday."

2. "My teacher are_______ so they always help everyone."

The correct answer is D. "funny." Assuming from the context that it's meant to be "My teachers are funny," however, if "helping" is a key trait, it might be inferred as kind, which was not correctly listed. Make sure to use "teachers are" for correct subject-verb agreement: "My teachers are funny, so they always help everyone."

Make sure to correct "teacher are" to "teachers are" for proper subject-verb agreement in the second sentence.