Fill in the gaps with the right form of the verb: Use: was able, have to, shouldn’t, will be able, couldn’t, could, can’t

Fill in the gaps with the right form of the verb: Use: was able, have to, shouldn’t, will be able, couldn’t, could, can’t1. When I looked at the test, I couldn\'t answer many questions.2. My camera doesn’t work, so I can\'t take any pictures.3. If I learn English, I will be able to understand people abroad.4. The singer had a sore throat. However, she was able to sing at the concert.5. He could sing very well when he was twenty.6. You shouldn\'t eat a lot of sweets.7. They didn’t have to go to school.