1. Main geology environmental issues include slope unstableness, geologic and physics influence of landslip, collapse, and debris - flow.

2. Not only his social criticism and sadomasochism subjects contradict and dispel to each other, his sadomasochism subject also discloses the writers unstableness in thought.

3. However, this petroleum cooperation is confronted with challenges from the economic unstableness due to a single industry structure in Sudan, and from the Darfur problem and the Western slanders.