9岁的外国小孩可以用"a 9-year-old foreign child"来表示。
"A 9-year-old"是形容词短语，用来修饰名词"child"，表示年龄是9岁。"Foreign"是形容词，用来修饰名词"child"，表示来自外国。
下面是一些例句：
"I have a 9-year-old foreign exchange student staying with my family this year."（我家今年有一个9岁的外国交换生。）
"My 9-year-old foreign neighbor is very curious and always asking questions."（我9岁的外国邻居非常好奇，总是问问题。）
"The 9-year-old foreign girl in my class is very shy, but she's starting to open up more."（我班上9岁的外国女孩很害羞，但她开始慢慢开朗起来了。）
"A 9-year-old"是形容词短语，用来修饰名词"child"，表示年龄是9岁。"Foreign"是形容词，用来修饰名词"child"，表示来自外国。
下面是一些例句：
"I have a 9-year-old foreign exchange student staying with my family this year."（我家今年有一个9岁的外国交换生。）
"My 9-year-old foreign neighbor is very curious and always asking questions."（我9岁的外国邻居非常好奇，总是问问题。）
"The 9-year-old foreign girl in my class is very shy, but she's starting to open up more."（我班上9岁的外国女孩很害羞，但她开始慢慢开朗起来了。）