Is this sentence pattern correct? "That task is hard to complete."

Question

Is this sentence pattern in the following two cases correct? Can you explain this structure more?

1. That task is hard to complete.
2. That event is impossible to imagine.

I thought it is only correct to say (It is + adjective + to do sth) because I was only taught this structure:

3. It is hard to complete that task.
4. It is impossible to imagine that event.

However, I know it's correct to say:

5. These foods are good to eat.(I know because this sentence is in a dictionary)

6. It is good to eat these foods.

Answer 1

Generally speaking, and "it is [adjective] clause followed by a to-infinitive can always be turned around:

It is hard to complete that task. = That task is hard to complete.

It is impossible to imagine that event.= That event is impossible to imagine.

It is easy to understand this structure.= This structure is easy to understand.

Both mean the same thing. HOWEVER, let's imagine intonation:

• It is hard [as opposed to easy or fun or something else] to complete that task. =

That task is hard to complete. [The emphasis in on the task]

Both structures are used in speaking but the second is most likely to be used when writing.