1. The cyclone has come. Many thousands of deaths. (RESULTED IN)  

  The cyclone has come, which resulted in many thousands of deaths.

2. Don't eat too much sugar. It creates health problems. (LEAD TO)

  Eating too much sugar can lead to health problems.

3. The weather was bad. That's why our departure delayed (BECAUSE OF) 

  Our departure delayed because of the bad weather.

4. There was damage to our property because of the fire. (RESULTED IN)  

  The fire resulted in the damage to our property.

5. They haven't reply our invitation so far. I think they are not coming. (SINCE)  

  I think they are not coming since they haven't reply our invitation so far.

6. The road condition is poor. There has been several accidents. (CAUSED)  

  The poor road condition has caused several accidents.