https://online2.tingclass.net/lesson/shi0529/0001/1240/21-02.mp3
https://image.tingclass.net/statics/js/2012
18. I am not sure whether I can gain any profit from the investment, so I can’t make a(n) ____ promise to help you.
A. exact B. defined C. definite D. sure
<investment>
investment 投資
investigate 調(diào)查
irrigate 灌溉
irritable 激怒的
navigate 航行
castigate 懲罰
mitigate 緩和，調(diào)解，減輕
</investment>
<sure>
sure 確信
insure 保險(xiǎn)
ensure 確保
</sure>
define 限定，下定義
final 結(jié)束的
refine 提純
finance 財(cái)政，資金
