According to the recent research,heavy coffee drinking and heart attack is not necessarily___and effect
The reason ___ he is absent is ___he has a bad cold.
_______ people died ______ starvation that year will never happen.
________ hard it might be, I will work it out.
You may give this message to _________ is at office.
You may have one of these; in other words, you have ______ you choose.