language、speech、tongue、dialect、idiom与slang这些名词均含“语言”之意。
language : 普通用词，含义广。指人的语言或文字，或动物的语言。既可指口头或书面语言，也可指手势语等。
- She does research into how children acquire language.
她研究儿童是如何习得语言的。 - Do you speak any foreign languages?"
你会说外语吗？ - I'm hopeless at learning languages.
我根本不是学语言的料。
speech : 特指人的口语，也指正式的讲话。
- Some expressions are used more in speech than in writing.
有些表达方式在口语中比书面语中用得多。 - I had to give/make a speech at my brother's wedding.
我得在我弟弟的婚礼上致辞。 - The Governor of New York delivered a rousing speech to the national convention.
纽约州州长在全国代表大会上作了激动人心的发言。
tongue : 书面用词，指人的语言，亦指人的母语。
- immigrants struggling to learn a foreign tongue
艰难学习外语的移民 - an ancient tongue
古老的语言
dialect : 指一种语言中，某一地方所特有的语言形式，即方言。
- a regional dialect
地区方言 - The poem is written in northern dialect.
这首诗是用北方方言写成的。
idiom : 指一种语言中一般由几个词结合成短语或句子的特殊表达方式，即惯用语、成语。也指方言。
- To "have bitten off more than you can chew" is an idiom that means you have tried to do something which is too difficult for you.
have bitten off more than you can chew 是一句习语，意思是试图承担力所不及的事。
slang : 指俚语。
- army slang
军队俚语 - a slang expression
一句俚语 - "Chicken" is slang for someone who isn't very brave.
chicken 是用来称呼胆小者的俚语。
