题目性质：自编仿真题——题目、材料、选项、数据与情境均为按课程标准与联招常见考点独立编写的原创仿真题，非真题原文，未取自任何题库、教辅或试卷；解析与采分点为教研整理，非官方评分标准。
一、考点定位与做题顺序
条件设空先分两类：真实条件（可能发生，主句用陈述语气）与虚拟条件（与事实相反，时态要「退一格」）。真实条件里几个连词各有分工：
if（如果）、unless（除非＝if … not，但只用于「若非此条件则不成立」，别硬套到所有否定句）、provided (that) / providing（前提是，书面、带约定口吻）、as long as（只要，强调持续条件）、in case（以防、万一，不是「如果」）、otherwise（否则，副词，常接 or 的语义）、but for / without（要不是，含蓄条件，主句多用 would have done）。
虚拟语气两套基本式：与现在相反 If + 过去式, … would + 动词原形；与过去相反 If + had done, … would have done。做题四步：判真实还是虚拟 → 找条件连词的语义分工 → 核主从句时态搭配 → 回读看是否「以防/否则/前提」。下面短文为自编示意文本。
二、逐题精讲
题1
题1 八空完形（每空四选一）
自编短文：The community greenhouse would open in April (1) ____ the roof panels arrived on time. Ms Iver said we could use the side beds (2) ____ we kept the paths clear. She also asked us to stack the spare glass (3) ____ a sudden frost damaged the young plants. (4) ____ the delivery had come a week earlier, we (5) ____ the first sowing before the cold spell; in fact it came late, so we had to wait. (6) ____ the delay, every seedling would have been ready by now. (7) ____ the volunteers had labelled each tray, the records would be in confusion now. She had also asked for a paper log; (8) ____, the sowing dates would have been lost.
(1) A. unless B. provided C. in case D. otherwise
(2) A. as long as B. in case C. unless D. but for
(3) A. if B. in case C. provided D. as long as
(4) A. If B. Unless C. In case D. Provided
(5) A. would finish B. would have finished C. finished D. had finished
(6) A. But for B. In case C. As long as D. Provided
(7) A. If B. Unless C. In case D. But for
(8) A. otherwise B. unless C. provided D. in case
解析
(1) B provided：「屋顶板按时到」是四月开放的前提，书面约定口吻，正是 provided (that)。unless 会变成「除非板子按时到，否则四月开放」——逻辑反了；in case 是「以防」，不接前提；otherwise 是副词，不能引导从句。(2) A as long as：「只要把通道保持畅通，就可以用侧畦」，强调持续条件。unless 会把许可变成否定条件；but for 后接名词不作连词；in case 语义不通。
(3) B in case：「把备用玻璃叠好，以防突降霜冻伤了幼苗」。这是本题最硬的信号：in case 表预防，不等于「如果」；选 A if 就成了「如果霜冻来了就叠玻璃」，动作顺序与目的全反。
(4) A If (5) B would have finished：后句「in fact it came late, so we had to wait」明示与过去事实相反，故用与过去相反的虚拟：If the delivery had come a week earlier, we would have finished the first sowing…。从句 had come 已给出，主句必须 would have + 过去分词；A 是现在/将来虚拟、C 是陈述过去、D 是从句形式，都不配。
(6) A But for：But for the delay, every seedling would have been ready by now＝「要不是延误，苗早就齐了」。but for + 名词 是含蓄条件，主句 would have been 正好配套；三个连词选项都不能接名词短语。
(7) B Unless：Unless the volunteers had labelled each tray, the records would be in confusion now＝「若不是志愿者给每个托盘贴了标签，记录现在就该乱了」。这里 unless 引导与过去事实相反的否定条件（＝if they had not labelled…），与后文 would be … now 构成错综时间虚拟（过去条件 → 现在结果）。选 A If 会把已发生的事说成未发生，与「记录没乱」的事实冲突；C、D 句法不合。
(8) A otherwise：We kept a paper log otherwise, just as she had asked 中的 otherwise 作副词，承接前文「照她要求另留一份纸质记录」。此处更自然的读法是「我们另外/照旧保留了纸质记录」，与 or / otherwise 的「否则、另作安排」语义相承；三个连词选项后面都没有从句，语法不成立。回读全篇：前提 → 持续条件 → 预防 → 过去虚拟 → 含蓄条件 → 错综虚拟 → 收束，八空的条件类型互不重复。
答案 (1) B provided (2) A as long as (3) B in case (4) A If (5) B would have finished (6) A But for (7) B Unless (8) A otherwise
采分点 八空各 1 分；(1) 说明 provided 表书面前提、unless 会逻辑反 1 分；(3) 说明 in case 表预防而非「如果」1 分；(4)(5) 判「与过去相反」并写出 had done / would have done 搭配 2 分；(6) but for + 名词为含蓄条件 1 分；(7) 说明错综时间虚拟（过去条件→现在结果）1 分；全篇条件类型梳理 1 分。
易错点 把 unless 一律当成 if not 硬套到 (1)；把 in case 当「如果」选 (3)；(5) 看到 had come 却选 would finish（漏过去虚拟）；(6) 用 In case 接名词；(7) 选 If 把已发生的事实说成假设；(8) 选连词却没有从句；忽略 in fact it came late 这一「与过去相反」的明示信号。
题2
题2 虚拟语气改错与三组近义辨析
(1) 改正下列三句（每句一处）：① If the delivery would have come earlier, we would have finished the sowing. ② If I would have known about the frost, I had covered the trays. ③ In case of the delay, every seedling would have been ready by now.
(2) 辨析三组：a) unless / if…not；b) in case / if；c) provided / as long as，各写一句能显出差别的自编例句。
解析
(1) ① If the delivery had come earlier, we would have finished the sowing.（与过去相反的虚拟，if 从句用 had done，不用 would have；would have 只出现在主句）。② If I had known about the frost, I would have covered the trays.（从句 had known、主句 would have covered，两处都要退一格；原句把 would have 放错位置、主句又用了 had covered）。③ But for the delay, every seedling would have been ready by now.（in case of 表「万一发生」，是预防，不表「要不是」；含蓄条件须用 but for + 名词 或 without）。规则一句话：if 从句不带 would；与过去相反用 had done ↔ would have done；「要不是」用 but for，不用 in case of。
(2) a) unless 是「除非/若非」，含「唯一例外」口吻，if…not 只是一般否定条件：Unless the panels arrive today, we cannot open in April — if they do not arrive, we shall simply move the sowing table, not cancel the plan.
b) in case 表「以防、万一」、动作发生在前；if 表「如果」、动作发生在条件成立之后：Stack the spare glass in case a frost comes; if a frost does come, cover the trays at once.
c) provided (that) 偏书面、强调「约定的前提」；as long as 强调「持续保持」：Provided the roof is repaired, we may use the greenhouse; as long as the paths stay clear, the side beds remain open.
三句都须在同一句里让两个结构各自显义，只列中文对应词不给满分。
答案 (1) ① had come；② had known / would have covered；③ But for the delay。(2) 三组例句见上。
采分点 三句改错各 1 分；写出「if 从句不带 would / had done↔would have done / but for 表要不是」三条规则各 1 分；三组辨析每组语义 1 分、例句显差别 1 分；例句时态搭配正确 1 分。
易错点 把 ① 改成 If…would come（现在虚拟）却没对上主句 would have；② 只改一处漏另一处；③ 改成 In case the delay…（仍表预防）；辨析时把 unless 与 if…not 说成「完全一样、随时可换」；in case 例句里把预防动作写在条件之后。
三、规律小结与对照表
| 结构 | 语义/时态 | 自编例 | 把关点 |
|---|---|---|---|
| provided (that) | 书面前提 | …opened provided the panels arrived | ≠ unless |
| as long as | 只要（持续） | as long as we kept the paths clear | 强调持续 |
| in case | 以防、万一 | in case a frost damaged… | 动作在前 |
| otherwise | 否则/另作安排 | kept a paper log otherwise | 副词，不接从句 |
| 与过去相反 | had done ↔ would have done | had come → would have finished | if 从句不带 would |
| 含蓄条件 | but for / without + 名词 | But for the delay, …would have been | 不用 in case of |
| 错综虚拟 | 过去条件→现在结果 | Unless…had labelled, …would be now | 时间不一致 |
| unless | 除非/若非（唯一例外） | Unless they had labelled… | ≠ 所有 if not |
条件设空的稳解，是先判真实还是虚拟，再给连词定分工：provided 是约定的前提、as long as 是持续保持、in case 是预防且动作在前、but for 后接名词表「要不是」、otherwise 是副词不接从句。虚拟语气记住「if 从句不带 would；与过去相反 had done ↔ would have done」，再留意「过去条件→现在结果」的错综时间。回读一遍看前后事实是否对得上，八空就不难。本篇短文、人物、机构与选项均为自编示意，不代表真实事件。
四、自测清单
- □ 先判真实条件还是与事实相反的虚拟；
- □ 找 in fact / in fact it came late 这类明示事实的句子定时态；
- □ if 从句绝不带 would；与过去相反用 had done ↔ would have done；
- □ in case 表「以防」、动作在前，不与 if 混；
- □ but for / without 后接名词，是含蓄条件，不用 in case of；
- □ provided（书面前提）与 as long as（持续保持）分开用；
- □ otherwise 是副词，后面不接从句；最后回读核对事实与结果是否一致。
