She won’t lose weight ___ she keeps a diet and takes exercise every day

Teaching as a career ________ to many people because of the long holidays.[ ]

I love singers who___ their own songs.

_____ to nuclear radiation, even for a short time, may produce variants (变异体) of genes in human bodies.

Doyoubelievethatpaperismade_______wood—Yes,Ido.Andyoucanseethatbooksaremade________paper.