ago we didn’t know this, but recent sciencestudy ________that people who don’t sleep well soon get ill.

What is the price of gas these days? —Oh, it ____________ sharply since last month

We should spend as much time as we can ______ English.

When did you become a volunteer for the elderly——Two years ago. I ______ this group since then.

It was a(n)______ party. We danced all night and then watched the sun coming up over the sea. No better way to welcome the New Year.