题目

Listening is just as _____ as speaking in language learning.A. important B. more importantC. most important D. the most important 答案：【答案】A【解析】句意：在语言学习中，听和说同样重要。考查同级比较。as……as，和……一样，用于同级比较，前一个as后面接形容词或者副词原形，故选A。 已知函数f(x)＝x2－ax＋4x＋4－a在x∈[0，3]时，f(x)＞0成立，求a的取值范围