The meat smells _________. You’d better throw it away.

---Can you work out the maths problem? ---Sorry, I can ______ understand its meaning.

–Do you like staying at home ________? --No, I don’t. That always makes me feel lonely .

Water is much more precious than electricity, for the water for drinking is__________.

I am too busy to listen to her ______ talking. She has talked for about two hours.