L I know how to use past modals could and had to. Complete the sentences with could and had to. I By the time Mozart was four he could play the violin. 1 By the time/Mozart/four/play the violin (could). 2 Marie/do chores/yesterday (had to). 3 Bobby/study English/last night (not have to). 4 The knights/pull the sword/out of the stone (could not). 5 John/ride a bike/when he was three (could not).