More than thirty groups of are working to develop a vaccine for COVID﹣19．（scientist）
Andrew was crazy about DIY， but he always made his room dirty and ． （tidy）
To our surprise， an 8﹣year﹣old girl became the of the dancing competition． （win）
On Teachers' Day， students usually make cards to thank teachers． （they）
When making a fruit salad， you'd better fresh fruit． （choose）