A: Hello, good morning.
B: Good morning.
A: Can you help me to lift this box right here?
B: Of course. Here, let me help you.
A: Thank you, now could you buy me a box of chocolate at the store next door please?
B: Ah, no problem. One moment, please.
A: Again, thank you for your help.
B: No problem at all! Now, would it be fine to exchange favors?
A: Of course!
B: Could you help me with my homework? I have it right here.
A: Sure thing! We're friends, so we should help each other.
Semoga bermanfaat :D