help:I want to know the differences

Actually, neither of them mean to put something together. I don't know where all of you folks came up with sth. and an abbreviation for something--but it isn't. If you mean the word something, then write the word something.

To gather means to accumulate by a conscious effort. To muster is more specific, and means to draw in all the men who are liable for military service, or to bring together all of the military units which one will use in a campaign. It is used figuratively to mean much the same as gather, but there is almost always a military overtone: "He mustered the forces of public opinion to push for the new law." "He mustered all of his supporters to make the meeting a success."

"Muster" often implies summoning or requesting, while "gather" usually has more to do with the physical act of collecting or bringing together.

For example, you would say "I like to gather seashells at the beach" rather than "I like to muster seashells at the beach" because collecting seashells at the beach is a physical act. However, you would say "I have to muster the courage" rather than "I have to gather the courage" because building up courage has more to do with summoning it in an abstract way.

Still, there are cases when either word works, like "Gather the troops"/"Muster the troops."

Heh... that's the second time of done this: post a reply to what I think is an unanswered post, only to find that someone was doing the same thing at the same time. Answering these grammar questions has become an informal race.

I'll be happy to leave the task entirely to you . . .