| 1. | The cell surface barrier had been broached .
细胞表面屏障被凿开。 |
| 2. | It could then have served as a trusty shield .
它就可以成为一个可靠的屏障。 |
| 3. | The new dam was a bulwark against future floods .
新堤坝是抵御未来洪水的屏障。 |
| 4. | The yanshan hills provide a natural defence for beijing .
燕山是北京的天然屏障。 |
| 5. | Winter now casts a shield before the russian armies .
这时，冬季为俄国的军队布下了一道屏障。 |
| 6. | A plastic membrane serves as selective diffusion barrier .
一层塑料薄膜起着选择性渗透屏障的作用。 |
| 7. | I leaned forward, straining to see through the barrier of light .
我向前探着身子，透过灯光的屏障极目张望。 |
| 8. | The river formed a natural blockade to the spread of the forest fire .
那条河成了阻止森林大火蔓延的天然屏障。 |
| 9. | Although membranes are barriers, they must also be considered to function in transport .
虽然膜是屏障，它们也具有转运的机能。 |
