How to join lines without changing their shapes

Hi. I’m learning some Rhino basics here, Ctrl+J worked for a lot of line joining but can’t make these lines (a single line through and a few rectangle lines to make a profile. I was hoping to get them joined to form a profile then use sweep 1 rail to make an object. But the shapes crash every time when I ctrl+join them as the photos before and after show. Please help.

Please post a .3dm (standard Rhino format) file with the lines. You can create the file using Export and selecting the lines. To upload the file either drag the file to where you type your post, or click on the vertical arrow icon above where you type your post.