Language, Idiom, Sentence and Phrase

 In English, "language" is not always the same that "idiom", and "sentence" is not the same that "phrase". 

- Languages and Idioms.

In Portuguese language, "idioma" ("idiom") and "linguagem" ("language") are the same thing, but in English language they are different things. A language is the system of sounds and words used by persons to express their thoughts, feelings, messages, information, etc. It is also the particular language system used by a people or nation. Some examples of languages: English, Spanish, Portuguese, Italian, French, etc.
An idiom can be:

• the style of writing, music, etc., associated with  a particular period, person or group of persons. In this case, there are popular, religious and classical idioms. 
• the language or dialect of a group of people or a country. 
• a phrase or sentence whose meaning is not clear from the meaning of individual words and must be learnt as a whole unit. 

In other words, an idiom is a particular case in which the meaning of a phrase is difficult or impossible to guess by looking at the meanings of the individual words it countains. For example, the phrase "We are in the same boat" has a literal meaning that is easy to understand and also has a common idiomatic meaning: "We are in a same situation."

Some other examples of idioms: 

• You are in my heart.  - I love you.
• I am so blue. I am very sad.
• Too many cooks spoil the broth. - Too many people involved in a same work will cause bad results.
• On your bike! - An expression to say to somebody to go away.

- Senteces and Phrases:

A sentence is a sequence of words that express a complete thought. For example: My house is yellow. 

So, a sentece has at least a noun phrase ("My house") and a verb phrase ("is yellow"). It means that a phrase is not a sentence because it lacks a subject or a predicate or both. A sentence has a subject and a predicate. 

A phrase does not give enough information about the predicate or the subject. A sentence always give complete information. So, all you have to know what is a sentence and what is a phrase is:

• Sentence: noun phrase + verb phrase
• Sentence: subject + predacate
• Phrase: only subject or only pedicate
• Phrase: sometimes it lacks the subject and the predicate.
  

In the next post: "Noun phrases and Verb Phrases".