Help

Firstly, for world 4 and 7, 你 MUST have mini 蘑菇 for this process.

Defeat the boss stage in world 2 and 5 with mini mushroom. World 5 is a bit trickier to beat with mini mushroom, so good luck!

In world 2, all 你 have to is ground pound the 毛虫, 毛毛虫 3 times. It's a bit trickier than it sounds but you'll do alright.

When 你 do defeat the boss stage, 你 will proceed in a pathway under the floor.

Good Luck!

^This.