Tu Youyou won Nobel Prize in Medicine for her discoveries that helped doctors fight malaria and _______ caused by roundworm parasites.

The hotel has been enlarged; ____, it’s service is improving

____is the weather like in Shaoxing today —It’s not too hot or too cold.

The machine _____ It hasn’t worked for years and no one wants to repair it

The left-behind kids（留守儿童）can’t see their parents __________ the parents come back home from work.