尽管天气很热，他还是保持着微笑。

Despite the hot weather, he still ___wears a smile.

门一直开着，让新鲜空气进来。

The door ___stays open to let in fresh air.

请固定这个摇晃的架子，防止它倒下。

Please ___secure the wobbly shelf to keep it from falling.