Fish use their swim bladder to float or sink in the water.

One part is important.

He was hesitant to start a new business, but I encouraged him by saying, 'There is a danger of tragedy in any attempt.'

We decided to start a new project by joining our companies.

His actions clearly contained a meaning of contempt.

A mass noun refers to a noun that cannot be counted.

She had a beautiful headdress on her head.

She called me 'Tom'.

There was a swelling on his leg.

There is nothing in his room.