Interlocutor: "Come on in. Have a seat. It's hot today isn't it?"

Hans: "Yes"

Miguel: "Yes, it is, isn't it? It's been hot all week."

Interlocutor: "Do you two know each other?"

Hans: "Yes, we are in the same school of languages."

Interlocutor: "Can you introduce me?"

Miguel: "Sure, I am Miguel, er … Miguel Carrera, this is Hans Bloeston."

Interlocutor: " I'm pleased to meet you. Have you known Miguel long, Hans?"

Hans: "Yes, we have, since the start of the term. We are often studying together, but we do not sit together in the class. I am by the front but Miguel likes to sit near the back."

Miguel: "I sit with a friend of mine back there. It's not such a good idea, you know, because he speaks Spanish too. If I sat with Hans then I would have to speak more English!"

Interlocutor: "Does your teacher let you speak Spanish in the classroom? Or German?"

Hans: "Sometimes, yes."

Miguel: "Or sometimes when we are doing exercises, we speak it quietly, even when we shouldn't. It's wrong, maybe, but it is a … do you call it a temptation?"

Interlocutor: "That's right. Do you have any brothers or sisters, Hans?"

Hans: "She is a sister - she is younger than me, Yes, I am well, eighteen years old, so she is now fifteen."

Miguel: "What's she called?"

Hans: "Her name is Freya."

Miguel: "That's a nice name. Is she learning English too?"

Interlocutor: "Come on in. Have a seat. It's hot today isn't it?"

Hans: "Yes"
This reply is a bit short - with a native speaker this reply would mean that the speaker wanted to finish the conversation.

Miguel: "Yes, it is, isn't it? It's been hot all week."
This is a better answer, because it shows competence with social speaking techniques (small talk).

Interlocutor: "Do you two know each other?"

Hans: "Yes, we are in the same school of languages."

Interlocutor: "Can you introduce me?"

Miguel: "Sure, I am Miguel, er … Miguel Carrera, this is Hans Bloeston."
This slight hesitation and correction is fine, because many native speakers would do exactly the same

Interlocutor: " I'm pleased to meet you. Have you known Miguel long, Hans?"

Hans: "Yes, we have, since the start of the term. We are often studying together, but we do not sit together in the class. I am by the front but Miguel likes to sit near the back."
The small errors in this statement will be marked as 'non-impeding errors' because they do not seriously interfere with communication.

Miguel: "I sit with a friend of mine back there. It's not such a good idea, you know, because he speaks Spanish too. If I sat with Hans then I would have to speak more English!"
The 'filler' here ('you know' ) is good style, and much better than using the filler 'errrrrr'!

Interlocutor: "Does your teacher let you speak Spanish in the classroom? Or German?"

Hans: "Sometimes, yes."

Miguel: "Or sometimes when we are doing exercises, we speak it quietly, even when we shouldn't. It's wrong, maybe, but it is a … do you call it a temptation?"
The examiner will not mark you down for being ambitious, especially if you use the right constructions to get feedback on possible errors - but do not be ambitious and incomprehensible.

Interlocutor: "That's right. Do you have any brothers or sisters, Hans?"
The interlocutor has decided to find out more about how Hans manages general conversation, so she rather suddenly changes the subject.

Hans: "She is a sister - she is younger than me, Yes, I am well, eighteen years old, so she is now fifteen."

Miguel: "What's she called?"

Hans: "Her name is Freya."

Miguel: "That's a nice name. Is she learning English too?"
Miguel is doing the right things to keep the conversation going without interfering with Hans' opportunity to express himself.

Summary

Hans is the weaker student. His replies are often too short, and some of his constructions ('A school of languages' instead 'of a language school' , 'She is a sister' instead of 'I have a sister') are rather clumsy. While Hans has made no serious errors, he has not shown fluency or particular skill either. Miguel seems relaxed and has made no serious errors, so the examiner has decided to give Hans a chance to demonstrate more of his language ability by asking him to speak about his family- while also testing how Miguel keeps the conversation going with someone who is not naturally talkative.