General:
* Não é bom: This is the most literal and direct translation.
* Não está bom: This means "it's not good" and is often used when referring to something that is not satisfactory.
* Mau: This is the Portuguese word for "bad".
More specific:
* Ruim: This is another word for "bad" and is more informal than "mau".
* Péssimo: This means "terrible" and is the strongest option.
* Fraco: This means "weak" or "poor" and is used to describe something that is not satisfactory.
* Insuficiente: This means "insufficient" and is often used to describe something that is not good enough.
Examples:
* Este filme não é bom. (This movie is not good.)
* O tempo não está bom hoje. (The weather is not good today.)
* Ela tem um mau humor. (She's in a bad mood.)
* Essa comida é ruim. (This food is bad.)
* Seu trabalho é péssimo. (Your work is terrible.)
* Ele é um jogador fraco. (He is a weak player.)
* A sua resposta foi insuficiente. (Your answer was insufficient.)
The best way to choose the right phrase depends on the specific context and the level of formality you want to convey.