since

Từ khi (đến hiện tại)

used for saying when something started or happened, often used with the present perfect tense

• since + past simple

Collocations since last year · since childhood

• I've been learning English since I was a child.

  Tôi đã học tiếng Anh từ khi còn nhỏ.

Vì, do (lý do)

used for giving the reason why something happens or is true

• since + clause

Collocations since then · since when

• I'm tired since I didn't sleep well last night.

  Tôi mệt vì tối qua không ngủ ngon.

Từ khi (đến hiện tại)

used for saying how long something has been happening or existing, often used with the present perfect tense

• since + past simple

Collocations since last week · since the beginning of the year

• They have been married since 1985.

  Họ đã kết hôn từ năm 1985.

Vì, do (lý do)

used for giving the reason why something happens or is true, often used in formal writing

• since + clause

Collocations since then · since when

• The company has been successful since it adopted new strategies.

  Công ty đã thành công kể từ khi áp dụng chiến lược mới.