He opened the windows to ________ the smell of tobacco.
We were talking and laughing, when our teacher came in and asked us what all the ______ was about.
The elevator _________ and we were trapped inside for half an hour.
--- Jim failed again in the maths examination. --- Don't scold him too much. _____ , he has tried his best.
The conference has been held to discuss the effects of tourism ______ the wildlife in the area.
The International Red Cross is ______ non-profit organization that cares for the wounded, sick and homeless in wartime, and victims of _____ natural disasters.