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Part IV Structure and Vocabulary () Directions: There are 20 incomplete sentences in this
Part IV Structure and Vocabulary () Directions: There are 20 incomplete sentences in this part. For each sentence there are four choices marked A),B),C) and D). Choose the ONE that best completes the sentence. Then mark the corresponding letter on the Answer Sheet with a single line through the center. 56. It is so difficult to _____ the bottom of the ocean because some parts are very deep.
A.explore
B.expose
C.expect
D.explain