Meshes and geometries can be arranged in a hierarchical structure. This merged objects are handled as one object
<three-canvas width="200" height="200" antialias="true" clear-color="#000000" default-light="true">
<three-camera position="0,0,20" look-at="0,0,0" controls="orbit"></three-camera>
<three-box width="1.5" height="1.5" depth="1.5" color="#ff0000">
<three-sphere-geometry radius="1"></three-sphere-geometry>
<three-box width="1" height="1" depth="1" position="1,1,0" rotation="0.2,0.2,0.2">
<three-box width="1" height="1" depth="1" position="0.5,0.5,0" rotation="0.2,0.2,0.2"></three-box>
</three-box>
<three-sphere radius="1" position="-1,1,1"></three-sphere>
</three-box>
</three-canvas>