Bad example:

The tabs on this page always change when I switch from one tab to another. Some tabs just disappeared, which made me really confused. Since it’s the main navigation bar of this site, it should keep uniform on each subpage.

My solution is put all these additional tabs in one group, then put aside as a submenu for each particular tab on the menu.

My sketch looks like this:

Good example:

Hook of umbrella

I took these pictures when I travelled to Japan last year. Since the room space is always limited, every little space has been taken full use of. I saw lots of smart industrial designs there. Take this umbrella hook for example. Actually it’s just a part of the intertalk doorbell. But we can easily tell its function from the shape of the slot and the little hook delicately designed in it. This design is so convenient and helps a lot to keep the room inside tidy and clean.