I have to take a lot of classes
必须───must;很多───quite a lot
We must never permit anything of the sort.───我们绝不允许存在这样的情况.
We must draw a clear distinction between ourselves and the enemy.───我们必须分清敌我.
We must have the wall redone.───我们必须将那面墙重修一下.
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.
Hospital operating instruments must be sanitary.───医院的手术器械必须是消过毒的.
We must look beyond for signs of change.───我们应该把目光放远,看到变化的迹象.
What goes up must come down.Isaac Newton
As the wind blows, you must set your sail.
We must make massive efforts to improve it.