useful

这本词典对我的英语学习很有用。

This dictionary is very ___useful for my English study.

我妈妈觉得智能手机比普通手机更有用。

My mum thinks a smartphone is ___more ___useful than a normal phone.

我认为地图是旅行中最有用的东西。

I think a map is the ___most ___useful thing when you travel.

这个应用程序对学习新单词很有用。

This app is ___useful for learning new words.

对我弟弟来说，电脑游戏比书更有用。

For my little brother, computer games are ___more ___useful than books.