| A tree is an organizational structure that has some useful properties for that purpose. |
| This is useful to control weeds and aerate the soil, which helps deter seedling diseases. |
| In the early days after the birth, it can be useful to set aside some time to rest when the baby sleeps. |
| As a result, the book reads like the first draft of what could have been a useful addition to the discussion of British town planning. |
| They will wield whatever power is necessary to do it, undermine whichever country when it seems useful to do so. |
| To him, money is a useful tool that humans will discard along the way, like the adz or the sword. |
