Timothy was driving as fast as he could. He ¹ (had to be / must have been) at the stadium by 10 o'clock. The weather was bad and he ² (couldn't see / couldn't have seen) very well. Moreover, the weatherman had said that it ³ (might get / might have got) worse. "I ⁴ (should have left / should leave) earlier," Timothy thought to himself. Just then, a car suddenly came from the side, but he ⁵ (couldn't stop / couldn't have stopped). He heard a Crash and everything went black. Then he heard a voice. " ⁶(Could you have heard / Can you hear) me?" Timothy nodded his head. "Are you in pain?" Timothy felt a terrible pain in his leg. "Yes," he said. "I think I ⁷ (might have broken / might break) my leg." "Don't worry," said the voice. "We have already called an ambulance. It ⁸ (should leave / should have left) by now."

Решение:

• 1. must have been — здесь мы предполагаем прошлое событие, которое произошло независимо от воли Тимоти, и используем модальный глагол совершенного вида.
• 2. couldn't see — описывается состояние в прошлом, когда он не мог видеть.
• 3. might get — прогноз на будущее, основанный на предыдущей информации (что погода может ухудшиться).
• 4. should have left — сожаление о прошлом действии, которое не было совершено (нужно было уехать раньше).
• 5. couldn't stop — описывается невозможность совершить действие в настоящем моменте (момент аварии).
• 6. Can you hear — вопрос о настоящем моменте (слышишь ли ты меня сейчас?).
• 7. might have broken — предположение о прошлом событии (возможно, нога сломалась в результате аварии).
• 8. should leave — совет или указание на то, что произойдет в ближайшем будущем (скорая должна выехать сейчас).

Ответ:

1. must have been
2. couldn't see
3. might get
4. should have left
5. couldn't stop
6. Can you hear
7. might have broken
8. should leave