Read these sentences and fill in the gaps with 'could', 'can', 'couldn't', 'can't'. 1. In my first year as a teacher, I almost lost my self-confidence because I (сюда что-то вставить) teach anything. 2. Before the nuclear disaster in the 1980's, people (cюда что-то вставить) grow everything in their gardens. 3. They (сюда что-то вставить) start their work when they want.