head; chief; first (occasion, thing etc); classifier for poems, songs etc[cedict]
轮
lúnㄌㄨㄣˊ
wheel; gear; (by) turn; rotate[cedict]
挑战
tiǎo zhànㄊㄧㄠˇ ㄓㄢˋ
challenge[cedict]
就
jiùㄐㄧㄡˋ
at once; right away; only; just (emphasis); as early as; already; as soon as; right away; then; in that case; as many as; even if; to approach; to move towards; to undertake; to engage in; to suffer; subjected to; to accomplish; to take advantage of; to g[cedict]
在
zàiㄗㄞˋ
(located) at; (to be) in; to exist; in the middle of doing sth; (indicating an action in progress)[cedict]