Which sentence correctly uses the subjunctive mood? A. If I am you, I will take the offer. B. I suggest that he studies harder. C. It's essential that she be informed. D. I wish I can finish the task tomorrow. 答案解析 核心考点：虚拟语气结构。正确答案C依据：'essential that+动词原形'是标准虚拟语气。错误选项分析：A/B/D均未使用虚拟语气结构。易错点：忽略建议/要求类动词后的虚拟语气规则。 正确答案：C