The disease, ________, could spread very fast.
They multiplied and filled the oceans and seas with oxygen, _____ encouraged the later development of early shellfish and all sorts of fish.
_____ is even more important is that as the earth cooled down, water began to appear on its surface.
It was not immediately obvious _____ water was to be fundamental to the development of life.
-- I wonder if I could possibly use your car for tonight? ---______. I'm not using it anyhow.
.--- Excuse me, can you tell me where the nearest bank is, please? ---______ Oh yes! It's past the office, next to a big market.