We can actually deduce here that the present perfect form of the given sentences will be:
1. I have read the instructions but I don't understand them.
2. He has taught English in five different countries.
3. She has cut her finger with a knife.
<h3>What is present perfect tense?</h3>
Present perfect tense is actually seen in a sentence as a form of a verb which reveals an action that was just carried out in the recent past and its effect is still seen and felt in the present. Also, present perfect tense refers to an action that talks about an indefinite time in the past.
The format that is usually employed in the use of present perfect tense is seen as:
For positive statement: Subject + have/has + past participle + the rest of the sentence.
For negative statement: Subject + have/has + not + past participle + the rest of the sentence.
Learn more about present perfect tense on brainly.com/question/886745
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