双引号和单引号都有。
双引号（1）表示文中的人说的话。"I"ve been thinking about this afternoon, you know,"said Halliday rather suddenly. （2）引用单词或短语。 How do you spell the word "across"?（3）不寻常的词语也常用引号，以引人注意。 The noun to which a relative pronoun refers is called the "antecedent" of the pronoun.关系代词所指代的名词唤作关系代词的“先行词”。（4）书名和诗文名也用引号。 Have you read, “The Jungle"? 你读过《屠场》吗？2. 单引号这两种引号没什么区别，但双引号更通用。单引号似多用在英国。She enjoyed the film "Madame curie".她很欣赏影片《居里夫人》。（英国习惯）She enjoyed the film "Madame Curie." (美国习惯）
