He did not come yesterday . He musst have been ill .
他昨天没来。他一定是病了。
The boy must be ill. Everything he ate came up again
这孩子一定是病了，他吃什么吐什么。
He looks pale. He has to be sick.
他脸色看来很苍白，一定是病了。
Bill must be ill; it's the only thing that accounts for his being away.
比尔一定生病了,这是惟一能解释他缺席的原因。
He looks very ill. He must have burnt the candle at both ends.
他看上去病得很厉害, 一定是劳累过度了。
He has had a bad illness, but he is better now.
他得了一场大病，可是现在他好多了。
"Oh, then he must be a bull!"
“那么他一定是‘多头’了
He must have been shipwrecked.
他一定是沉船遇难了。
I must be sick,@ he thought, @But I must study for that test.
“我一定是病了，”他想，“但我必须好好学习，为考试作准备。”
When I saw him tearing out of his front door like a bat out of hell and into the phone - box I thought his wife or one of the kids must have taken ill or something.
我看到他一下子拉开门，拼命地跑进电话亭，我想一定是他妻子或孩子病了，或发生了什么事。
His poor health was a contributory factor in his decision to retire.
体弱多病是他决定退休的一个原因。
He dreamt not only that one cow was sick, but that all his cattle had fallen ill.
他梦见不单是一头奶牛病了，而是他的所有牛群都病了。
Whenever anyone was ill he installed himself as sicknurse.
要是有人病了，他就俨然象是一个护士去照料他。
The poor old man must be dying; he's certainly past praying for.
可怜的老汉一定是要死了，他肯定是救不活了。
On the fifteenth of August, he decided to start working. If he fell ill again, he swore, he would drown himself in the river.
到八月十五，他决定出车，这回要是再病了，他起了誓，他就去跳河！
but he is troubled because his mother has a terminal illness and life at home must be a struggle.
但是现在他很苦恼，因为他母亲的病已到了晚期，家里的生活一定很艰难。”
He took two arrows,and he must have hit his marker.
他中了两箭,一定是偶然碰到了传导器
Well, it does not seem like it. He must have forgotten .
唔，看样子不会了。 他一定是忘记了。