滿嘴跑火車 [满－－－车]

Jyutping mun5 zeoi2 paau2 fo2 ce1
Pinyin mǎn zuǐ pǎo huǒ chē

Definitions (Wiktionary)
  1. verb, figuratively
    To make reckless or exaggerated statements; to talk baselessly; to blabber on and on

滿嘴跑火車 [满－－－车]

Jyutping
Pinyin mǎn zuǐ pǎo huǒ chē

Definitions (CC-CEDICT)
  1. (idiom) to have a glib tongue
  2. to talk big
Examples (Tatoeba—Mandarin-English)
  1. Mandarin
    汤姆满嘴跑火车。
    湯姆滿嘴跑火車。
    tāng mǔ mǎn zuǐ pǎo huǒ chē 。
    • Tom is talking nonsense.