满口应承

滿口應承
mǎnkǒuyìngchéng
to promise readily

CEDICT

满口答应。

重編國語辭典

Entry Composition

1 满口 mǎnkǒu
  1. a full mouth of (sth tangible)
  2. to have the mouth exclusively filled with (a certain language, lies, promises etc)
  3. (to agree etc) unreservedly
2 应承 yìngchéng
  1. to agree (to do sth)
  2. to promise