Теорія:

Study the infromation about the adverbs of time.

1. This type of adverbs tell use when something happens. We can refer to days of the week without this, last, next, on:

I saw them Monday( + last/on Monday).
  
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This morning can refer to:
-Now
-Earlier
-Later on today.

I feel good this morning.

Remember: tonight, tomorrow night, last night, the day before yesterday, the day after tomorrow.

2. Still and yet mean ‘until now’, we often use these words with the present perfect.

Still - to show continuity, mainly in affirmatives and questions. We can use still in the negative for special emphasis.

She is still waiting for her plane.
  
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Jim hasn’t still written to me.

Yet - in questions and negatives and often at the end of the sentence.

Have you done your homework yet?
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