31.   But what causes them and what can be done to prevent them?

32.   Can you tell me how to get these stains out and what we can do to prevent future staining of this kind?

33.   Child magazine contributing editor Stephanie Wood writes on the latest research and what all parents of young babies should do to prevent SIDS.

34.   Certainly, much remains to be done to prevent discrimination against those who have chosen to be wives and mothers.

35.   Despite hundreds of studies, researchers still do not have much definitive information about the causes of breast cancer and what women might do to prevent it.

36.   Despite measures taken by bomb squads in the capital and elsewhere, little can be done to prevent suicide missions, according to security officials.

37.   Doctors know that hand-washing is the most effective thing one can do to prevent contagion.

38.   For example, there is little that can be done to prevent sabotage on miles and miles of track.

39.   Gendarmes and firemen returning from the rescue scene Wednesday said nothing could have been done to prevent the tragedy.

40.   Have there been deaths or serious injuries, what happened and what has the camp done to prevent a recurrence?