Поставьте модальный глагол или его эквивалент в нужном времени, обращая внимание на обстоятельства времени.

1) If your cat is old, you (to be) to check its claws regularly as they (may) grow too long and hurt its paw. 2) When he was a child he (can) treat his pet. 3) They (have) to translate the whole text to understand the meaning of it. 4) Next lesson he (may) be late, he (must) to visit a doctor. 5) A farmer (to be) to milk his cows twice a day.