Раскройте скобки и поставьте глаголы во времени Present Perfect Continuous

1.Let me out! I ( sit )here since yesterday

2.I can’t hold this book any more. Professor ( read) it for 8 hours already

3.Where is the top? I (climb) for a long time and haven’t reached the top yet

4. It ( rain) heavily since early morning, and the rain hasn’t stopped yet.

5 .I’m very cold. I (wait) for my friend for an hour, and he hasn’t come yet

6.The birds ( sing) their lovely songs since spring came.