Meaning : Pull hard.
Example :
The prisoner tugged at the chains.
This movie tugs at the heart strings.
Meaning : Tow (a vessel) with a tug.
Example :
The tugboat tugged the freighter into the harbor.
Meaning : Move by pulling hard.
Example :
The horse finally tugged the cart out of the mud.
Meaning : Pull or strain hard at.
Example :
Each oar was tugged by several men.
Meaning : Struggle in opposition.
Example :
She tugged and wrestled with her conflicts.