Question

5. His failure in the experiment suggested that he        his teacher's proper instructions. (follow)

他实验的失败说明他没有听从他老师的正确指令。

Answer 1

5. had not followed此处suggest意为"表明，显示"，而不是"建议"之意，因此，从句不用虚拟语气，而应用陈述语气。