le (了)is the simple perfective marker, while guo(過) is the experiential marker. Both markers are added as suffixes after the verb to express the actualised or terminated event bounded by a reference time, but the use of guo(過) further implies discontinuity to the present, which is not a requirement in the use of le (了) (Sun 2006; Smith, 1991).
For example:
- 我學了中文. ‘I learnt Chinese (and I may still be learning Chinese).’
- 我學過中文. ‘I learnt Chinese (and I am no longer learning Chinese)’
guo(過) implies that the situation is discontinued with a gap between event time and reference time, so 我學過中文 indicates that the event is discontinued with the present and hence “learning Chinese” is not related to the reference time.
zai(在) and zhe(着) is another confusing pair. zai(在) is the progressive marker and zhe(着) is the imperfective marker. These two markers in Chinese express the imperfective viewpoint. An imperfective viewpoint views a situation as unbounded, ongoing and durative (Sun, 2006). The major difference lies in that zai(在) is used for active or dynamic actions, while zhe(着) is used for continuous, lasting action and state(Smith, 1991).
For instance:
- 她在穿衣服。‘She is putting on clothes.’
- 她穿着衣服。‘She wears clothes.’
穿 can be both dynamic or stative. The first sentence with zai(在) implies a dynamic action and that there is a change in the clothes she is wearing. The second sentence with zhe(着) implies a stative action and that she has been wearing her current clothes for a while without any change.
Reference
Smith, Carlota. 1991. The Parameter of Aspect. Boston: Kluwer Academic Press.
Sun, C. (2006). Chinese: A Linguistic Introduction (1st ed.). Cambridge University Press