The suffixes ཡག་ and རྒྱུ་ are associated only with the present-future form of the verb:

• ཞུ་ཡག་ but not *ཞུས་ཡག་
• ཟ་ཡག་ but not *བཟས་ཡག་
• བལྟ་ཡག་ but not *བལྟས་ཡག་

The suffix ཡག་, which is sometimes spelled ཡས་, does not occur in Literary Tibetan, which instead uses the nominalizer པ་. The form རྒྱུ་, on the other hand, is used both in Spoken Tibetan and in the literary language.