When “awhile” is spelled as a single word, it is an adverb meaning “for a time” (“stay awhile”); but when “while” is the object of a prepositional phrase, like “Lend me your monkey wrench for a while” the “while” must be separated from the “a.” (But if the preposition “for” were lacking in this sentence, “awhile” could be used in this way: “Lend me your monkey wrench awhile.”) [/color]

e.g

I watched them while they were playing soccer.

He came in while we were dancing.

I listened to music While she slept.

While I was talking on the phone,my brother knocked the door.

While I walking slowly in the evening , someone frighted me by touching behind me

a big explosion occured while i was cooking.