begin (something) energetically and enthusiastically
（積極熱情地）開始，著手
he launched into a two-hour sales pitch.
他發(fā)動(dòng)了一場(chǎng)兩小時(shí)的銷售宣傳。
make a start on a new and challenging enterprise
開創(chuàng)，啟動(dòng)（新而難的事）
she wasn't brave enough to launch out by herself.
她沒有勇氣獨(dú)自闖蕩一番。