“USA? Britain? Which country is____(good) to study in?” We often hear such discussion. As China opens its door, it is a dream for many Chinese students to study abroad. They want to learn about the outside world.

    It's true that studying abroad can help students develop____(they). Their foreign language skills will____ (improve) and it may be easier to find jobs.

    But there are problems____ should be considered. Language is the first. Students must spend a lot of time____ (learn) another language.

    Students must also learn____ (live) without parents' care and deal with all kinds of things they didn't have to do before, like looking after themselves. There are ____ (report) about Chinese students abroad running into an ocean of difficulties____ giving up in the end. When they have to take care ____ themselves, it is hard for students to study well.

    Finally, studying abroad brings a heavy burden to the family. For most Chinese parents, the cost of studying abroad____ (be) very high. But is it worth it?

假定五对等位基因自由组合．则杂交组合AaBBCcDDEe×AaBbCCddEe产生的子代中，有一对等位基因杂合、四对等位基因纯合的个体所占的比率是（　　）