1.I know why it must happen.

2.I know why must it happen.

1.I see why he must work more .

2.I see why must he work more .

1.I need to know what must I prepare .

2.I need to know what I must prepare .

a

an

Their

There

Them

They

1.inhappy

2.unhappy.

1.unregular

2.irregular

1.impatient

2.unpatient

1.inable

2.unable

1.I don't know why is it happening.

2.I don't know why it's happening.

1.I need to know what I must prepare.

2.I need to know what must I prepare.

1.Do you know where he lives ?

2.Do you know where does he live?

1.Do you know why was she so angry?

2.Do you know why she was so angry?

1.for

2.about

1.about

2.with

1.from

Taller

Tallest

More tall

don't

doesn't

Aren't