n. 鑰匙;(打字機等的)鍵;關鍵,線索,秘訣;(音樂的)調;
vt. 鍵入;鎖上;調節…的音調;提供線索;
vi. 使用鑰匙;
adj. 關鍵的;主要的;
??? 情景例句
Yeah, Grandpa,
對呀, 爺爺。
Forgive me for interrupting, but I have a question.
對不起我插個嘴,我有一個問題。
it requires 97 per cent less energy to travel the quarter of a million miles from the Moon to Earth-orbit than the 200 mile-journey from Earth's surface into orbit!