著 is a durative and stative marker. For instance, ‘他在房子里坐著’ and ‘他們彼此深愛著’.
著 occurs with only stage-level predicates not individual-level predicates. For example, ‘*他一直聰明著’ is ungrammatical.
著 co-occurs with atelic event. For instance, ‘他喝著茶’ and ‘他喝著一杯茶’.
著 is mainly used with dynamic activity verb, such as 坐,拿.