1 (wiktionary) 2 (vi.wikipedia) 3 (en.wikipedia) 4 (glosbe)

Compounds Expand your vocabulary by studying more complex words built by the 'core words'.
Etymology Explore the origin of the 'core words'.
Wordsense Learn about the wordsenses of the english term.

TOPIK 11000 KOREAN WORDS

☆ FALLING; DROPPING; PLUNGING sự rớt, sự tụt ☆ FALL BEHIND; LAG BEHIND rớt lại, tụt lại
HSK 3.0 11000 CHINESE WORDS

ENGLISH 6000 THEME WORDS

OXFORD 5000 CORE WORDS

TANAKA 6000 CORE WORDS

tụt to slide down, fall behind, drop behind
[ tụt ] : to slide down, fall behind, drop behind

American students are falling behind in math .

Học sinh Mỹ đang tụt lại phía sau trong môn toán.
I fall behind him in this respect .

Tôi tụt lại phía sau anh ta về mặt này.
She's far behind in her studies .

Cô ấy bị tụt hậu rất xa trong học tập.