Beside, besides. Beside means next to. Besides means in addition to.

Right: John lives beside his mother.
Right: Besides the daughters, there are three sons.

Between. Do not use between when referring to more than two objects.

Wrong: There is bad feeling between the members of the class.
Right: There is bad feeling among the members of the class.

Blowed. Do not use blowed for blew or blown. There is no such word.

Best. Do not use best when only two objects are referred to. Use better. Best should be used only when more than two are referred to.

Wrong: He is the best of the two brothers.
Right: He is the better of the two brothers.
Right: He is the best of the three brothers.

Bound. Do not use bound for determined.

Wrong: He was bound to go skating.
Right: He was determined to go skating.
Right: He bound himself to pay three hundred dollars.

But. Do not use but after a negative in the sense of only. See §46.