In May 2011, Americans spent 53 billion minutes on Facebook, ______ it the most popular U.S. website.
| A．making | B．made | C．to make | D．having made |
________ I couldn't fully understand what he wanted to show in his paintings, I thought his works were quite impressive.
| A．As | B．Since | C．If | D．While |
Jim came back early last night. It was not yet eight o'clock ________ he got home.
| A．before | B．that | C．when | D．until |
If we work with a strong will, we can overcome any difficulty, ________ great it is.
| A．what | B．how | C．however | D．whatever |
Life is filled with things we have no control over, ________ ourselves, we can control.
| A．for | B．and | C．so | D．but |
I'll make some sandwiches, just ________ we get hungry later.
| A．even if | B．as though |
| C．if only | D．in case |