A complex sentence contains one independent clause and at least one dependent clause. The difference between an independent clause and a dependent one is that the former can stand alone as a sentence as it represents a complete thought. The ungrammaticality of sentence A proves this point. As you can see, without the independent clause (B), the dependent clause (A) does not represent a complete idea, it depends on the main clause to complete its meaning (C).
A) *Because it is cruel
B) The death penalty should be abolished
C) Because it is cruel, the death penalty should be abolished
President Kennedy did not initially adrress the issue of civil rights. He did little to support the different bills. He chose not to make civil rights issues important during the time because he was afraid of losing support from southern voters. After he was elected president he started taking more action though
