Was ist das für eine Konstruktion?

He "must have missed" the train.

Was ist das für eine Zeit?

[finta]

Supposition and deduction, unregistered!

He must be about thirty. I'm supposing this because of his looks, clothes etc. now, but I do not know for sure. Present time.

He must have been about thirty when he died. I don't know his exact age when he died , but am supposing he was about thirty. Past time.

I think you can use 'mussen' in a similar way in German!

Hope this helps!

finta