отрицательное предложение. (Обратите внимание, что предложения могут быть в настоящем или прошедшем времени!)
Пример:
+She could speak English last year.
?Could she speak English last year?
+Yes, she could.
-No, she couldn’t.
--She couldn’t speak English last year.
She can learn poems by heart.
They could read when they were 5.