when是什么意思音标:英 [wen]美 [wɛn]

conj. 当...的时候
adv. 何时, 什么时候
pron. 什么时侯
n. 时间

adv. At what time; -- used interrogatively.
adv. At what time; at, during, or after the time that; at or
just after, the moment that; -- used relatively.
adv. While; whereas; although; -- used in the manner of a
conjunction to introduce a dependent adverbial sentence or clause,
having a causal, conditional, or adversative relation to the principal
proposition; as, he chose to turn highwayman when he might have
continued an honest man; he removed the tree when it was the best in
the grounds.
adv. Which time; then; -- used elpptically as a noun.