Are "sous" "au-dessous de" synonyms?

Could I say:
"le chien dort sous la table" (the dog sleeps under the table)
and also: "le chien dort au-dessous de la table"??
Somehow I like the sentence with "sous" better.
Also: which is correct?
"je te n'aime pas" or "je ne t'aime pas"

"je t'ai aimé" or "j'ai t'aimé"

2 answers

:) I read your 2nd post first.

Sra (aka Mme)

P.S. Thanks for YOUR help!
Merci beaucoup de votre aid; as for "my help", I am very glad if I am able to help others.