“There were a thousand other fruits which Adam and Eve could eat, but this one was forbidden.” What does the underlined（划线的） word mean?

-Mike wants to know if_______ a picnic tomorrow. -Yes. But if it_______, we'll visit the museum instead.

  ---__________ is it from here to Yangzhou Museum? --- About 20 minutes by bike.

—I don’t care what the teacher thinks. — But I think you _______.

This is the most important gift _______ I have received from my parents.