| Those trees used to stand like sentinels on either side of the path leading to the bandstand from the Glass House. |
| The day lilies in the ditch north of Five Corners are orange summer sentinels, fully at attention. |
| The Blackcrest Mountains were very tall here, and they stood like foreboding sentinels with their black peaks protruding like worn teeth. |
| It is the habit of crows to perch like sentinels on the tops of isolated trees, where they can see what is going on in all directions. |
| The spinach, arugula, tatsoi and mache all appeared like green sentinels standing up to Old Man Winter's blanket of white snow. |
| Rousing slumbering T cells is the job of dendritic cells, the sentinels of the immune system. |
