- Left side
- S1 [L1, ...]! ⇒ forces that all anotations match the description
- S1 [L1, ...]!! ⇒ forces to have just one anotation matching the description
- S1 [L1, ...] [L2, ...] ⇒ needs to match all the given descriptions
- Right side
- S1* ⇒ rewrites what matched without changes
- S1 [L1, ...]- ⇒ deletes the given anotation
