To Connect Surfaces
1. Select two or more surfaces to connect and click 
Style > 
Surface Connect. The Surface Connection tab opens, and connection symbols are displayed along the surface boundaries.
Style > Surface Connect. The Surface Connection tab opens, and connection symbols are displayed along the surface boundaries.2. Move the pointer over the connection symbol, right-click, and choose a connection type.
3. For auto-connect operations only, a message input window opens. Read the information and click Yes to accept the changes and make the connection. The surfaces are connected.
4. Click 
OK.
OK.