like: one week → →
to last a week, be one week long ☊ 
kéo dài một tuần ☊ exactly one week after ☊ đúng một tuần sau khi ☊ It will be ready in a week's time (= one week from now). ☊ in ☊
We've put the wedding forward by one week. ☊ put sth forward ☊
The exams start a week today/today week (= one week from now). ☊ today ☊