How to join the discontinue surfaces together to form a solid brep to slice in grasshopper

Hi my friends,
I wonder if anyone can help me to solve the surface joining problem I have right now. I modeled several discontinue surfaces and tried to trim them to join together, but it could not allow me to trim. Some surfaces were not able to join together. I am not very good at modeling with rhino. I think because of this, I can not slice them to form brep surface. Can anyone help? (331.2 KB)
ChengDuClub_mTrim2c1_UL.3dm (4.7 MB)