keep in sight (?.)
- and listen
- be vigilant
- be watchful
- bear in mind
- eye
- eyeball
- follow
- gaze at
- have a looksee
- have regard for
- hold in mind
- hold in view
- keep alert
- keep in mind
- keep in view
- keep under observation
- keep vigil
- keep watch
- look
- look about one
- look after
- look at
- look lively
- look on
- look out
- look sharp
- look upon
- never nod
- observe
- qui vive
- reckon with
- reconnoiter
- regard
- scout
- spy upon
- stop
- take account of
- take cognizance of
- take heed of
- take into account
- take into consideration
- take note of
- take notice of
- view
- watch
- watch out