to rub / to grind / to polish / to sharpen / to wear down / to die out / to waste time / to pester / to insist
磨
=
石
+
麻
:
Mahatma Gandhi (m) has been tied down in the observatory's kitchen (o2) with ropes made of hemp (麻). He uses a stone (石) to patiently rub (磨) through the ropes.
to rub against / to walk slowly / (coll.) to freeload
蹭
=
足
+
曾
:
The firefly (曾) is too lazy to fly on its own. To get to the other side of the engine's bathroom ((e)ng4) it is freeloading (蹭) by hanging on to a football (足) thrown by the King of Chu (c).