Since I like fishing.This is a sentence fragment because it is a dependent clause. "Since" is a subordinating conjunction, and this sentence can't stand alone.We could correct this sentence by removing the word "since," so the sentence would simply read "I like fishing." I am the subject, like is the verb, fishing is the object.We could also correct this sentence by joining the dependent clause with an independent clause: I am going to the lake, since I like fishing.
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