1. 两个单词之间没有什么区别。
    There's ____________ ____________ between the two words.
2. 他说得很慢以便我们能听清楚。
    He spoke very slowly ____________ ____________we could hear clearly.
3. 我能开阔学生们的视野，使他们了解外面的世界。
    I can ____________ ____________ my students' eyes to the outside world.
4. 人们将用信用卡代替纸币。
    People will use credit cards ____________ ____________ paper money.
5. 这件套服那么贵，他买不起。
    The suit is ____________ ____________ ____________ he can't afford it.