23. Which preposition is commonly used with the present perfect tense to indicate duration?
24. Which of these is NOT a use of the present perfect?
25. What is the correct negative contraction for "He has not studied for the exam"?
26. Complete the sentence by choosing the correct form of the verb in the present perfect.
27. Complete the sentence by choosing the correct form of the verb in the present perfect?
28. Complete the sentence by choosing the correct form of the verb in the present perfect?
29. Complete the sentence by choosing the correct form of the verb in the present perfect?
30. Complete the sentence by choosing the correct form of the verb in the present perfect?