04-01
Zero Conditional
零条件句💡 概念 Concept
If + present, present — for general truths and scientific facts. Both parts are always true.If + 一般现在时，一般现在时 — 表示普遍真理和科学事实，两个部分都恒成立。
📐 规则 Rules
结构
If + present simple, present simple: If you heat ice, it melts.
If + 一般现在时，一般现在时：如果你加热冰，它会融化。
用途
facts, rules, habits: If I am late, my teacher is angry.
事实、规则、习惯：如果我迟到，老师会生气。
✏️ 例句 Examples
If you freeze water, it becomes ice.
水结冰就会变成冰。
If plants get no sunlight, they die.
植物没有阳光就会死。
If I drink coffee at night, I can't sleep.
我晚上喝咖啡就睡不着。
⚠️ 常见错误 Common Mistakes
❌ If you will heat ice → no will in the if-clause: If you heat ice...❌ if 从句不用 will。
❌ If she is late, she misses the bus (general rule) — both present.❌ 一般规律：从句和主句都用一般现在时。
04-02
First Conditional
第一条件句💡 概念 Concept
If + present, will + base — real future possibilities. The condition is possible and the result is a likely future.If + 一般现在时，will + 原形 — 表示现实的可能。条件有可能实现，结果是可能的未来。
📐 规则 Rules
结构
If + present simple, will + base: If it rains, we will stay home.
If + 一般现在时，will + 原形：如果下雨，我们就待在家里。
从句时态
Never use will in the if-clause: If I have time (not will have).
if 从句绝不用 will。
✏️ 例句 Examples
If you study hard, you will pass the exam.
如果你努力学习，就会通过考试。
We will cancel the trip if the weather is bad.
如果天气不好，我们就取消行程。
If she calls, I will tell her the news.
如果她打电话来，我会告诉她这个消息。
⚠️ 常见错误 Common Mistakes
❌ If it will rain → present in if-clause: If it rains.❌ if 从句用现在时：If it rains。
❌ If I study, I pass (real future) → first conditional needs will: I will pass.❌ 表示未来可能结果用 will。
04-03
Second Conditional
第二条件句💡 概念 Concept
If + past, would + base — unreal present or future situations. Imagining something that is not true now.If + 一般过去时，would + 原形 — 表示与现在或将来事实相反的假设。
📐 规则 Rules
结构
If + past simple, would + base: If I had money, I would travel.
If + 一般过去时，would + 原形：如果我有钱，我会去旅行。
be 动词
were for all persons in formal English: If I were you...
正式语中 be 用 were：如果我是你……
含义
The situation is unreal or unlikely now.
表示目前不真实或不太可能的情况。
✏️ 例句 Examples
If I were you, I would take the job.
如果我是你，我会接受这份工作。
If she spoke English, she could work abroad.
如果她会说英语，她就能在国外工作。
If we had a car, we would drive there.
如果我们有车，我们会开车去那里。
⚠️ 常见错误 Common Mistakes
❌ If I was you → use were in conditionals: If I were you.❌ 虚拟条件中 be 用 were：If I were you。
❌ If I have money, I would travel → mixed structure: If I had money...❌ 从句用过去时：If I had money...
04-04
Third Conditional
第三条件句💡 概念 Concept
If + past perfect, would have + past participle — unreal past situations and regrets. The event did not happen.If + 过去完成时，would have + 过去分词 — 表示与过去事实相反的假设与遗憾。
📐 规则 Rules
结构
If + had + pp, would have + pp: If I had known, I would have helped.
If + had + 过去分词，would have + 过去分词：如果我早知道，我就会帮忙。
含义
The past event did not happen — pure regret or counterfactual.
过去的事没有发生 — 纯遗憾或反事实。
✏️ 例句 Examples
If she had studied, she would have passed.
如果她学了，她本来会通过的。
We would have arrived earlier if we had left on time.
如果我们准时出发，我们本来会更早到达。
If I had seen the sign, I wouldn't have turned left.
如果我看到了标志，我就不会左转。
⚠️ 常见错误 Common Mistakes
❌ If I knew, I would have helped → past condition needs past perfect: If I had known.❌ 过去假设从句用 had known。
❌ If I had studied, I would pass → time mismatch; use would have passed.❌ 主句也要用 would have + 过去分词。
04-05
Mixed Conditionals
混合条件句💡 概念 Concept
Mixed conditionals combine different times: past condition + present result (If I had studied, I would be rich now) or present condition + past result.混合条件句结合不同时间：过去条件 + 现在结果（如果我当初学了，现在就会很有钱）或现在条件 + 过去结果。
📐 规则 Rules
过去条件+现在结果
If + had + pp, would + base: If I had taken that job, I would be in Shanghai now.
If + had + pp，would + 原形：如果我当初接受那份工作，现在就在上海了。
现在条件+过去结果
If + past simple, would have + pp: If I weren't afraid of flying, I would have gone.
If + 过去时，would have + pp：如果我不怕坐飞机，我早就去了。
✏️ 例句 Examples
If she had studied medicine, she would be a doctor today.
如果她当初学医，现在就是医生了。
If I were braver, I would have spoken up.
如果我更勇敢，我当时就会说出来。
If he hadn't missed the train, he wouldn't be stuck here now.
如果他没误了火车，现在就不会困在这里。
⚠️ 常见错误 Common Mistakes
❌ Mixing without a clear time reason → keep each half on its own timeline.❌ 混合必须理由清晰：半个句子一个时间线。
❌ If I had studied, I would be passing → use base form for present result: would pass.❌ 现在结果用 would + 原形。
04-06
Alternatives to If
if 的替代表达💡 概念 Concept
unless = if...not; provided that / as long as = on condition that; in case = because something might happen.unless 表示【如果不】；provided that / as long as 表示【只要】；in case 表示【以防】。
📐 规则 Rules
unless
unless + positive verb = if...not: Unless you hurry, you'll miss it.
unless + 肯定动词 = 如果不：除非你抓紧，否则会错过。
provided / as long as
condition: You can go as long as you finish first.
条件：只要你先完成就能去。
in case
precaution: Take an umbrella in case it rains.
预防：带把伞以防下雨。
✏️ 例句 Examples
You won't pass unless you study.
不学习你就不会通过。
I'll lend you the car provided that you drive carefully.
只要你小心驾驶，我就把车借给你。
Keep the receipt in case you want to return it.
留着收据，以防你想退货。
⚠️ 常见错误 Common Mistakes
❌ unless you don't hurry → unless is already negative; no double negative.❌ unless 本身就是否定，不能再加 not。
❌ as long as you will finish → present in condition clauses.❌ 条件从句用现在时。
04-07
I Wish / If Only
wish / if only 愿望句💡 概念 Concept
wish + past simple = present regret (unreal now); wish + past perfect = past regret; wish + would = a wish about someone's future behaviour.wish + 过去时 = 对现在的遗憾；wish + 过去完成时 = 对过去的遗憾；wish + would = 希望某人将来改变行为。
📐 规则 Rules
现在遗憾
wish + past simple: I wish I knew the answer.
wish + 过去时：我希望我知道答案（可惜不知道）。
过去遗憾
wish + past perfect: I wish I had studied harder.
wish + 过去完成时：我多希望当初更用功。
行为愿望
wish + would: I wish you would stop talking.
wish + would：我希望你别再说话了。
✏️ 例句 Examples
I wish I were taller.
我希望自己更高一些。
She wishes she had said yes.
她后悔当时没答应。
If only the bus would come!
要是公交车能来就好了！
⚠️ 常见错误 Common Mistakes
❌ I wish I am taller → unreal wish needs past: I wish I were taller.❌ 愿望句用过去时：I wish I were taller。
❌ I wish I have studied → past regret: I wish I had studied.❌ 过去遗憾用 had + 过去分词。
04-08
Production and Editing
综合运用与改错💡 概念 Concept
Choose the conditional by reality: real fact → zero; real future → first; unreal now → second; unreal past → third. Check both halves.按现实度选条件句：事实用零条件句；现实未来用第一；虚拟现在用第二；虚拟过去用第三。检查前后两半。
📐 规则 Rules
选型
Is it true? → zero. Possible? → first. Unlikely now? → second. Impossible past? → third.
恒真→零；可能→第一；现在不可能→第二；过去不可能→第三。
检查
Never will after if. Match the tenses in both halves.
if 后不用 will；两半时态要匹配。
✏️ 例句 Examples
If I won the lottery, I would buy a house. (unreal now)
如果我中彩票，我会买房。（现在虚拟）
If you heat metal, it expands. (fact)
金属受热会膨胀。（事实）
If we leave now, we will catch the train. (real future)
如果我们现在出发，就能赶上火车。（现实未来）
⚠️ 常见错误 Common Mistakes
❌ If I would win the lottery → no would in if-clause: If I won...❌ if 从句不用 would。
❌ Mixing zero and first without a reason.❌ 不要无理由混用条件句类型。
PR
课堂练习 Practice
选自 GramLingo 题库Q1If you ___ water to 100 degrees, it ___.
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Q2She ___ the train if she ___ earlier.
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Q3Choose the correct sentence:
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