A Puncture

‘Why is my car tyre flat?’ I asked my husband, who was sitting on the sofa.
‘Because it’s not full of air.’ He replied.

‘Yes, but why is it not full of air?’
‘Because the air is not inside the tyre.’

I took a deep breath, and enquired patiently. ‘But why is the air not inside the tyre?’
‘Because the air is outside the tyre.’

I took a pause. ‘If the air was inside the tyre, how is it that now it is outside the tyre?’
‘Because the air has escaped.’

‘But how has it escaped?’ I was beginning to get cross.
‘It escaped through a hole.’ He replied unemotionally.

‘How does the tyre have a hole in it?’ I asked with dangerous calm.
‘Because it has a puncture.’

‘How does it come to have a puncture?’
‘Because you parked it on top of the garden rake.’

I was furious, but without an answer.