someone's heart is in their mouth

US /ˈsʌm.wʌnz hɑːrt ɪz ɪn ðer maʊθ/
UK /ˈsʌm.wʌnz hɑːrt ɪz ɪn ðer maʊθ/
"someone's heart is in their mouth" picture
1.

jantung berdebar kencang, sangat gementar

to feel very nervous or frightened

:
When the roller coaster started, my heart was in my mouth.
Apabila roller coaster bermula, jantung saya berdebar kencang.
Her heart was in her mouth as she waited for the exam results.
Jantungnya berdebar kencang sambil menunggu keputusan peperiksaan.