Otherwise means if not. Otherwise is essentially a transitional adverb. It does not connect two clauses. It merely shows how a statement is related to what has already been said.
- We must hurry; otherwise we will be late for the movie.
- We must hurry. If we dont, we will be late for the movie.
- You must work hard; otherwise you will fail the test.
- She must sort things out; otherwise, she will find herself in deep trouble.
- I hope the weather improves. Otherwise, well have to cancel the picnic.
- They must be interested in buying the apartment. Otherwise, they wouldnt have asked about the prices.
A transitional adverb does not connect two clauses. It merely ensures the flow of ideas between sentences and paragraph.
- He must be quite intelligent. Otherwise, he wouldnt be able to solve such a difficult problem.
- He must be intelligent; otherwise, he wouldnt be able to solve such a difficult problem.
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