for / since

Grandpa has been sick ____________ a long time. He has been in the hospital _____________ last May.

• for；since

• since；for

• for；for

• since；since

Ken is at his office. He has been there _____ 7:30.

• for

• since

Linda and John have been married _____ ten years.

• for

• since

Linda and John have been married _____________ ten years ago.

• for

• since

I have known the Browns ____ I was a child.

• for

• since

I’ve learned a lot from my teachers _____________ I came to the class.

• for

• since

I have learned swimming _____________ I was seven years old.

• for

• since

I have studied English ______________ 1999.

• for

• since

I have been a student __________ fifteen years. During this time, I haven’t had any working experience.

• for

• since

Jenny has been blind ___________ she was born.

• for

• since