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There are so many new words in the text so that I have _____in understanding it .
A many difficulties B much difficulty
這題為什么不能用A呢？在同一試卷里見到了下面一句子
I never give up no matter how many difficulties I meet .
為什么第一題里就不能用其可數形式來指具體困難呢？老師，請指教。