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Questions & Answers about Eu estou cansado desde ontem.
Why do we use estou instead of sou cansado?
Portuguese has two verbs for “to be”: ser and estar. You use ser for permanent traits or identities (e.g. “Eu sou alto”), and estar for temporary states or conditions. Feeling tired is temporary, so you say estou cansado.
Why is the present tense estou used here, even though the tiredness began yesterday?
Unlike English, Portuguese often uses the simple present to describe a state that started in the past and continues now. By adding desde ontem (“since yesterday”), you make clear when the state began. There’s no need for a separate “present perfect” form to express “I have been tired since yesterday.”
What is the role of desde in this sentence? Could I use há instead?
desde + a specific starting point (a date, time or event) marks the moment when something began. E.g. desde ontem = “since yesterday.”
há + a duration expresses how long something has lasted. E.g. Estou cansado há um dia = “I’ve been tired for a day.” Both are correct, but they focus on slightly different perspectives (starting point vs. total duration).
Can I drop the subject pronoun eu and just say Estou cansado desde ontem?
Yes. Portuguese is a pro-drop language: you only include eu for emphasis or to avoid ambiguity. In most contexts, Estou cansado desde ontem is perfectly natural.
Why is the adjective cansado masculine? What if a woman says this sentence?
Adjectives in Portuguese agree in gender and number with the subject. A male speaker says cansado, a female speaker says cansada, and a group of women would be cansadas.
Could I say a partir de ontem instead of desde ontem?
Yes, a partir de ontem (“as of yesterday” or “starting yesterday”) is grammatically correct but slightly more formal or emphatic. desde ontem is more idiomatic for everyday speech when expressing a continuous state.
Are there any differences between European Portuguese and Brazilian Portuguese for this sentence?
No major structural differences: both varieties say Estou cansado desde ontem. You might hear minor pronunciation or intonation differences, but the grammar and word choice remain the same.