“如果”是人类在思考能、可能或原本可能发生的事情时最常想到的词语之一。在英语中，我们会使用引导条件句的单词“if”来表达这类想法。你会使用“混合条件句”、“真实条件句”吗？来测试自己对英语语法难点之一 — 条件句的掌握。

1. How many categories of conditional sentences are often taught?

a) two (‘first’ and ‘second’ conditional)

b) three (‘first’, ‘second’ and ‘third’ conditional)

c) four (‘zero’, ‘first’, ‘second’ and ‘third’ conditional)

d) five (‘zero’, ‘first’, ‘second’, ‘third’ and ‘mixed’ conditional)

2. Conditional sentences or questions are constructed from two clauses – a conditional clause and a main clause. What difference is there if the order of the two clauses is switched? 

a) The meaning of the whole sentence changes.

b) The main clause must be written differently if it comes first.

c) There is no difference at all

d) When the main clause comes first, we do not use a comma between them

3. Which of these is an example of a ‘mixed’ conditional?

a) If I had grown up in France, I would speak French.

b) If I grow up in France, I will speak French

c) If I grew up in France, I would speak French

d) If I had grown up in France, I would have spoken French

4. What verb form do we normally use in the 'if' cluase of first conditional sentences?

a) present simple

b) present continuous

c) present perfect

d) all of the above

5. In a ‘first’ conditional structure, we do not usually put a ‘will’ form in the conditional clause. However, it can happen, but only under particular circumstances. What are they? 

a) If the speaker wishes to make a polite request

b) If the speaker wishes to be insistent

c) If the speaker is talking about the result of a possible future action

d) All of the above

6. "If I'd known it was so expensive, I wouldn't have bought it." What does this mean?

a) I knew it was expensive. I bought it.

b) I didn't know it was expensive. I bought it.

c) I didn't buy it. It was expensive.

d) I bought it. It wasn't expensive.

1) d, 2) d, 3) a, 4) d, 5) d, 6) b.