You Do Need power plug adapter while traveling from Marshall Islands to Lebanon.

Here is Why You Need An Adapter

The outlet and plug type used in Lebanon are C, D and G and in Marshall Islands are A and B. This is how they look like.

Marshall Islands

In Marshall Islands, outlets of type A and B are in use.

Type A

Type B

Lebanon

In Lebanon, outlets of type C, D and G are in use.

Type C

Type D

Type G