Lili ________ be at home. She has gone to the farm to pick apples.
mustn’t
can’t
must
can
There _____ a number of people at the square in the morning, the number _____ over 1,000.
I _____________ his letter for a week.
We will go climbing _______ it ________ tomorrow.
My mother _______________ my aunt called her.
He is _______ clever boy that he can solve _____ many difficult problems.