I had to wait at the railroad crossing for a long, long, very long train.
No, You cannot use but to start a sentence.
With a pen :)
Condescension is a long word and i am putting it in to a sentence.
Example sentence - We walked quietly in the long hallway.
Example sentence - Her hair was long and silky to touch.
"I received the goods only long after they were due."
The antenna on the ant was long
That area will be radioactive for a long, long time.
Long enough to learn how to spell author and use it properly in a sentence.
It is possible to use control group in a sentence as long as it does make sense.
There is a stiff sentence for harbouring a criminal. How long will you be harbouring your boat here?
The cream was meant to be long-lasting so she put it away for future use.