Emphasis in English. Part 2: Expressing Annoyance

We use the Simple Present to express habits: She always smiles at people. 
But what happens when you want to express an annoying habit or the idea that something irritating or shocking always happens?

We use the Present Continuous with words such as "always" or "constantly".
Its meaning is like Simple Present, but with negative emotion; there is often an element of criticism with this structure

Compare these sentences:

• Juan always asks questions about the lesson. ( a fact)
• Juan is always asking questions about the lesson. ( annoying)
• My teacher always loses her keys.(a fact)
• My teacher is always losing her keys! (annoying)
  

More examples
•    She is always coming to class late.
•    He is constantly sending text messages. I wish he would stop.

•    I don't like them because they are always having arguments.