Revision questions: modals

What is the past form of the following sentence? He must go home. (1) He had to go home or (2) He must have gone home?
How can the same modal appear in both clauseA group of related words containing a subject and a verb.s of the following second conditional sentence? If I could swim, I could be a sailor.
Does the sentence If he was hungry, he would go to the nearest take-away express present or past timeA concept which is related to our perception of reality; that part of existence which is measured in seconds, minutes, hours, days, weeks, etc.?
How many opposites of can't can you think of?
What is the difference between the following two sentences? (1) I didn't need to include a CV in my application. (2) I needn't have included a CV in my application.
What could this sentence mean? He might have died.
What is the difference between possibility and certainty/uncertainty?
Can we use a perfectThe aspect expressing completion. E.g.: He’s finished university. infinitive after a modal auxiliaryA helping verb used with main verbs to express mood, voice and tense. E.g.: I can't stand when I am disturbed. ("can", "am") expressing past time?
What is the difference between these two sentences? (1) You shouldn't have come. (2) You needn't have come.

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