WORD CHOICE: seem, appear, look and sound.

SEEM and APPEAR have the same meaning but APPEAR is more formal:

They seem upset.
This appears to be a good solution.

You use LOOK to say how someone or something seems to you when you look at them:

Maureen looked tired.
That book looks good.

You use SOUND to say how someone or something seem to you when you hear or read about them, or hear them:

She sounds a lovely person.
The party sounded great.
He sounded tired.

SEEM can be followed by an adjective or an adjective and a noun:

She seemed happy.
He seems a nice man.

SEEM can also be followed by a verb in the infinitive:

His story seems to be true.
You seem to think it’s my fault.

SEEM can be followed by as if or as though but not just by as:

It seems a small thing, but it’s very important. (NOT it seems as…)
It seemed as if he wanted us to leave. (NOT it seemed as he wanted…)