must 和 have to的用法區(qū)別

1. must 側(cè)重于個(gè)人意志和主觀上的必要。have to 側(cè)重于客觀上的必要，可用于現(xiàn)在時(shí)、過(guò)去時(shí)和將來(lái)時(shí)。例如：

I know I must study hard. 我知道我必須努力學(xué)習(xí)。

My brother was very ill, so I had to call the doctor in the mid-night.

我弟弟病得厲害， 我只得半夜里把醫(yī)生請(qǐng)來(lái)。

I haven't got any money with me, so I'll have to borrow some from my friend.

我身上沒(méi)帶錢，只好向朋友借點(diǎn)了。

He said they must work hard.他說(shuō)他們必須努力工作。

2. have to可以用于多種時(shí)態(tài)；而must只用于一般現(xiàn)在或?qū)?lái)。例如：

The composition is due to hand in this morning, so I had to finish it last night.

作文今天早晨到期，因此我不得不昨天晚上完成。