Hello,
Happy New Year!
I’m modeling this chair, I used Bezier curve to create the upper part, but wondering if I can adjust the bending, because the shape is like a wave. Could the Simple Deform Modifier (Bend) do multiple bending? Or any other better method to do the modeling? Thank you!
Personally, I’d box model it with proportional editing turned on to get the curves, then throw it under a SubD surface.
Very quick example that took around a minute.
Two ways for doing this come into my mind.
On layer one you’ll see the one that utilizes curves that define paths for subdivided planes who’s edge count is controlled by a modifier.
On the second layer you’ll find a much simpler alternative but less precise, this one just uses lattice to define it’s shape.
Keep in mind that both Seat objects use the same mesh, so before applying any changes to them make sure you make the mesh of that specific object single-user-copy. .blend file
Don’t crop the images while asking questions, it leaves most of the information out from the rest of the interface, including the information about what you’re showing.
Proportional editing helps to edit existing geometry and also to make the forms but that’s not the only tool. Here are four ways to make it. Curves give the most controls over the resolution and form but is by far the hardest to set up.
Textures might need some rotating and aligning but otherwise, looking good
I will need to update it, Thanks for your help 
