By (+ a time) = not later than: I sent the letter to them today, so they should receive it by Monday. (= on or before Monday, not later than Monday) We’d better hurry. We have to be home by 5 o’clock. (= at or before 5 o’clock, not later than 5 o’clock) Where’s Sarah? [...]
used to + infinitive, -ing, noun
I. used to + infinitive used to + infinitive is only used in the past: it has no present form. We use it to talk about past habits and states which are now finished’ I used to smoke, but I’ve stopped She used to be very shy. To talk about present habits and states, we [...]
