New pinpoints:
Apenas para entender o uso de QUE e DE com TER.
(Just for understanding the usage of QUE and DE with TER.)
Onde TER é usado em/no lugar de PRECISAR?
(Where TER is used in replace of PRECISAR?)
Pelo = per + o
So, even tough (not so uncommonly) you can listen to this, it's wrong to use 'pelo o', 'pela a', etc.
Desculpa, senhor, mas...
Desculpe, senhor, mas...
The correct would be 'desculpe', since 'senhor' agrees with the 3rd-person singular. But, at least in my state, it's common to listen to the first one too and it's very acceptable. Both are not the best options if you truly want to apologize, since 'desculpar' is overused in informal and semi-formal contexts.
The common is to say 'mas eu ainda...' and not 'mas ainda eu...'
The common is to say 'tarefa de casa' for a generic task (for example, a homework). 'Tarefa da casa' makes us think of a specified task.
Dor is feminine. 'A dor', not 'o dor'.
The adjectives agree in number with the nouns, so:
'As frases corretas'
'Os dentes muito grandes'