2. 表示不可避免性或肯定性
這時must—般只用于肯定句,主要是推測現(xiàn)在或?qū)肀厝话l(fā)生的事情,可譯為 “必然”、“必定”等。如:
* The power output of a transformer must be less than the power input because of unavoidable losses in the form of heat.
變壓器的輸出功率必然小于輸入功率,因為熱的損耗無法避免。
* For some centuries before there was experimental proof, it was believed that the speed of light must be finite.?
在有實驗證明以前的好幾個世紀(jì),人們就已相信光的速度必定是有限的。
* At any instant, the difference between the transistor-capacitor current and the output current must be the supply current.
在任何瞬間,晶體管一電容電流與輸出電流之差必定是電源電流。
must后也可跟“have +過去分詞”結(jié)構(gòu),表示對過去已發(fā)生事情的推測,可譯 為“一定”、“一定已經(jīng)”等。如:
* They must have removed these fuses.
他們一定已經(jīng)更換了這些保險絲。
* An electric timer must have been wired into this system.
這個系統(tǒng)一定是安裝了電子定時器。
責(zé)任編輯:admin