GRE Text Completion: ETS Official Practice 150-GRE OP150:填空 - 51DCGN0D510D55JBO

We have yet to (i)____________ the assessment of Canada's biodiversity. Most of the vertebrates have been assessed, but our challenge will be the assessment of invertebrates and plants. This task is (ii)____________ not only because of the high number of species, but also because of the diversity, each species requiring a different approach. A. initiate B. repetitious C. complete D. trivial E. limit F. daunting