You must keep the room clean

必须───must

The stew must be boiled up before serving.───炖肉必须煮熟才能上桌.

You must hand over your passport before you leave.───离境前必须交回护照.

I must think over this, I have known for years that it was in the cards.───我得仔细考虑考虑,许多年来, 我就知道这是可能的.

No mathematician is infallible; he may make mistakes, but he must not hedge.───没有一位数学家是一贯正确的; 他可能会犯错误, 但他绝不会回避任何一个问题.

The realisation that the murderer must have been a close friend came as a shock.───意识到杀人凶手一定是个密友,大家都很震惊.

There must be something wrong with my left arm, which is asleep.───我的左臂发麻,一定出什么问题了.

We must have the wall redone.───我们必须将那面墙重修一下.

I must ask you to tone down your remarks; they are giving offence to some of our visitors.───我们必须要求你说话语气和缓一些, 因为你的话得罪了一些客人.

A dancer must throw herself heart and soul into every performance.───舞蹈演员对每一场演出都必须尽心尽力.

We must look beyond for signs of change.───我们应该把目光放远,看到变化的迹象.

Sorry, I must have dialled the wrong number.

Desperate diseases must have desperate cures.

The fish is rotten; you must not eat it.

A full cup must be carried steadily.

He that will thrive must rise at five.

We must make massive efforts to improve it.

We must reinforce the troops at the front.

If you want knwledge, you must toil for it.

One must drink as one brews.