John...answer the teacher's questions because he knew the material
a) need
b)can
c) could
d) ought
Answers
John could answer the teacher's questions because he knew the material
a) need
b)can
c) could ✔
d) ought
Explanation:-
➺ Could: we use could to express an ability or an lack of ability in past time. So, here we can use could to express the John's ability to answer the teacher's question.
The sentence is stating a past situation, here knew is used which is a past form of 'know', so we can conclude that a past scenario is stated there.
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• Need: need without "to" is used in negative and interrogative sentences. In the affirmative, we use need to to express necessity. Also, need isn't a past form.
• Can: in our statement, can could be used if the situation stated there was in present tense/form.
• Ought: ought is used when some public interest work is done for charity or public service. So it doesn't suit in that sentence.