1. Once we get down to the oil, it usually flows to the surface because great pressure, either from gas or water, is pushing it.
    一旦到达油层，石油就会由于地下巨大的压力流到地面上来，这种巨大的压力来自地下天然气或水。

2. That porpoises will save drowning men by pushing them to the surface,
    认为海豚会把快要淹死的人托到水面，救人性命；

3. If they can't get you for pushing drugs, maybe they can deport you for denying you pushed them before.
    如果他们不能因为非法销售毒品而抓住你，他们也许会因为你否认自己以前非法销售过毒品而把你驱逐出境。

4. In fact, there is no scientific basis for theories pushing the genetic superiority of any one population over another.
    实际上，那种认为某一种群比另一种群的基因更优越的理论是毫无科学根据的。