1. Shall I bring you a cup of tea?

> Would you like a cup of tea? 

2. My sister is more hard-working than me.

>I don’t work so hard as my sister does .

3. Do you have a better refrigerator than this?

> Is this the best refrigerator you have?

4. Finding an apartment in a big city is not easy.

> It is not easy to find an apartment in a big city.

5. February often has 28 days.

> There are often 28 days in February.