:Truly speaking, even if English learners have memorized thousands of words and dozens of grammar rules, they can still ________upon a mysterious invisible block.A:equippedB:intentionallyC:invisibleD:stumble答案: stumble18、
:Truly speaking, even if English learners have memorized thousands of words and dozens of grammar rules, they can still ________upon a mysterious invisible block.A:equippedB:intentionallyC:invisibleD:stumble答案: stumble18、