Non-finite forms of a verbA part of speech that expresses an action or a state. E.g.: John seldom plays tennis. do not indicate the timeA concept which is related to our perception of reality; that part of existence which is measured in seconds, minutes, hours, days, weeks, etc. of the actionA general term expressing that somebody or something does something, however, they do have aspectA verbal category relating an action to the passage of time. It can express duration or completion..

• The aspect of infinitives
• The aspect of participles
• The aspect of gerunds

The finite / non-finite distinction
Non-finite verb forms The aspect of infinitives