SOS on IBM WebSphere Studio

The first time when I installed it on my computer, I can see various Perspectives, such as Java, Bean, JSP. After I uninstalled it and reinstalled it, I only can see very few Perspectives. Even I clicked Windows->Open perspectives->other, I still can see only a few of them. I did not see any error message when I reinstalled it. Can anyone help me on this asap. Thanks a lot!