This was no ordinary class. The students who came together were all science or engineering professors at Cornell University. They had interrupted their research to accept an invitation to take part in an unusual experiment: "an interesting week of poetry." This class was part of a study to answer the questions: Why is science difficult for many nonscience students? What can teachers learn about teaching if they take a class that is not in their field? The students in the poetry class listened to lectures and took notes. They had reading tasks and had to write three short papers. All students noticed one thing - the importance of spoken words. In science and engineering classes, the instructors put tables and drawings on the blackboard. But in this poetry class, the instructors just talked. They didn't write anything on the board. The scientists and engineers noticed one similarity between science and poetry. In both subjects, students need to find layers   of meaning . Some layers are simple, clean, and on the surface; other layers are deeper and more difficult. This search for different levels of meaning doesn't happen much in undergraduate  science classes, but it is important later, in graduate school. And it is always important in humanities . Both the poetry instructors and their students learned something about teaching from this experience. One poetry instructor, for example, now sees the importance of using informative as he teaches. Most of the scientists agreed on several points. First, humanities classes might help science students to see patterns and decide which information is important. Second, the poetry class was fun. One engineer decided, "We need to change the way we teach engineering to make to make it an enjoyable experience for students." But perhaps the most important result of the experience was this; All of the professors began to think about how they teach and how they cam teach better. Finding levels of meaning is  _  .
important for graduate students in humanities difficult for graduate students in humanities common for undergraduate students in science easy for undergraduate students in science.