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【題目】With the help of Air Classroom, students ________ keep learning even with schools closed.

【題目】Drugs are harmful to people's physical and mental health. We teenagers must ________ them.

【題目】—Pingtang Bridge has the highest concrete bridge tower in the world.

【題目】As we all know, using public chopsticks ________ necessary when we eat with others.

【題目】After-school activities help students gain more skills and teach ________ to care about others.

【題目】In difficult times, there are always national heroes ________ step up and bring people hope.

【題目】Even if we learn something well, we will forget it ________ we use it.

【題目】—Tara, what's your favorite ________?

【題目】Chinese volleyball player Zhu Ting has become ________ world-recognized sports star.