Ability/Possibility
Five years ago, I ___________ play the piano.
Five years ago, I couldn't play the piano.
We have enough milk in the fridge so we not ___________ buy some more.
We have enough milk in the fridge so we don't have to buy some more.
She might can join us for dinner if she finishes work early.
She might join us for dinner if she finishes work early.
They are required to wear a uniform.
They must wear a uniform.
They have to wear a uniform
A: Someone is knocking at the door.
B: It ____________ be the pizza delivery man. I ordered a pizza.
It must / might be the pizza delivery man. I ordered a pizza.
We ___________ speak English well now.
We can speak English well now.
Time is not on our side. We (must, mustn't, don't have) hurry.
Time is not on our side. We must hurry.
He should attends the meeting on time.
He should attend the meeting on time.
Is it conceivable for her to arrive by noon?
Might she arrive by noon?
Could she arrive by noon?
May she arrive by noon?
B: It must / might be the pizza delivery man. I ordered a pizza.
A: I know you ordered a pizza. But it ___________ be him, because you ordered the pizza five minutes ago.
I know you ordered a pizza. But it can't be him, because you ordered the pizza five minutes ago.
The volleyball team ___________ go to the Olympics this year if they are lucky.
The volleyball team could go to the Olympics this year if they are lucky.
Mary gave me a letter to send. I not ___________ forget to mail it.
Mary gave me a letter to send. I mustn't forget to mail it.
He must be able finishing the project on time, considering his experience.
He must be able to finish the project on time, considering his experience.
She is outlawed from entering the restricted area.
She mustn't enter the restricted area.
She can't enter the restricted area.
A:I know you ordered a pizza. But it can't be him, because you ordered the pizza five minutes ago.
B: Yes, you are right. Then it ___________ be your sister.
B: Yes, you are right. Then it might / could / may be your sister.
I ___________ not run that fast when I was six years old.
I couldn't (could not) run that fast when I was six years old.
You not _____________ wash those carrots. They've already been washed.
You don't have to wash those carrots. They've already been washed.
Are you able help me with my luggage?
Are you able to help me with my luggage?
They have the proficiency to solve the complex problem.
They can solve the complex problem.
They are able to solve the complex problem.
B: Yes, you are right. Then it might / could / may be your sister.
A: No, it ___________ be my sister, she's out of town.
No, it can't be my sister, she's out of town.
I think I ___________ help you learn math if you study hard.
I think I can help you learn math if you study hard.
He will be having lessons for another two hours. We ______ not visit him now.
He will be having lessons for another two hours. We mustn't visit him now.
You mustn't do tomorrow's homework. It's for the next class.
You don't have to do tomorrow's homework. It's for the next class.
You are not compelled to attend the optional seminar.
You need not attend the optional seminar.
You don't have to attend the optional seminar.
A: No, it can't be my sister, she's out of town.
B: Well, then just open the door; it ___________ be important.
Well, then just open the door; it might / could / may be important.