Moreover, both khɨn3 and up can be used to denote non-directional meanings (such as man4 caj1 khɨn3 'be more confident' and speed up), and this is also true with the pair loŋ1 and down (such as sin3sut2 loŋ1 'end' and close down).
while khɨn3 and loŋ1 occur as main verbs or subsidiary verbs in serial verb constructions in Thai, up and down rarely occur in verb slots in English; they usually appear as satellites accompanying verbs.