5. Put the verbs in brackets into the Present Perfect or the Present Perfect Continuous Tense: 1) We (meet) ___ before? 2) I (try) ___ to catch the waiter's attention for about 15 minutes now. 3) She (study) ___ English for a year and (learn) ___ many words and expressions. 4) I (not/hear) ___ about him since yesterday. 5) I (look) ___ for him since I finished my lesson but I (not/find) ___ him. I (be) ___ to his office and to the laboratory but he isn't there. 6) I (be) ___ up here since about six. I (wander) ___ around for hours. 7) I expect these young men (inform) ___ you who I am. 8) I really don't know what you (do) ___ there all this time. 9) I (love) ___ you ever since I first saw you. 10) And that's where they (stay) ___ ever since. 11) They (struggle) ___ with this problem for about a month and they (solve) ___ it.

1. Have we met before?
2. I have been trying to catch the waiter's attention for about 15 minutes now.
3. She has been studying English for a year and has learned many words and expressions.
4. I haven't heard about him since yesterday.
5. I have been looking for him since I finished my lesson, but I haven't found him. I have been to his office and to the laboratory, but he isn't there.
6. I have been up here since about six. I have been wandering around for hours.
7. I expect these young men have informed you who I am.
8. I really don't know what you have been doing there all this time.
9. I have loved you ever since I first saw you.
10. And that's where they have stayed ever since.
11. They have been struggling with this problem for about a month and they have solved it.

Continuous forms emphasize duration or an ongoing activity; perfect forms emphasize a completed result, experience, or state.