Accept is always used as a verb, primarily meaning to agree to take something (like a job or gift).
Example : I accepted the job with Hinkhoj. / You should accept my apology.

Except is normally used as a preposition, meaning but, or as a conjunction, meaning with the exception of, only or not including. In the case of a conjunction, except is often followed by that.
Example : Everyone will be there at the party except Hari./ Any girls and boys with asthma are excepted from this program.

Expect is almost always used as a verb, primarily meaning to believe something will happen.
Example : With his new car, Danny expects to have a new girlfriend by the summer.