When visiting a home in the United States, it is not customary to bring ___________. Instead, _____________ are standard in the United States.
举一反三
- There are _____ states in the United States.
- The Constitution of the United States of America is the Supreme law of the United States.
- There are 50 stars on the national flag of the United States. They represent today's 50 States of the United States.
- Not until the dedication of Yellowstone Park in the late nineteenth century（）a national park. A: the United States had B: did the United States have C: when the United States had D: the United States having
- 中国大学MOOC: There are ________________ (a number）states in the United States.