to knock at the gate (old); to make an approach; to invade; to attack the goal (sports)

to kowtow (traditional greeting, esp. to a superior, involving kneeling and pressing one's forehead to the ground); also written 磕頭|磕头[ke1 tou2]

call-in (loanword)

to bow in salute; to kowtow

spike (volleyball)

to kowtow in salute

to visit (esp. one's superiors)

to knock on a door

(literary) to inquire; to ask; question

to kowtow; also written 磕頭|磕头[ke1 tou2]

to kowtow

to kneel three times and kowtow nine times (formal etiquette on meeting the emperor)