My favorite landform is the high mountin.
>> My favorite landform is high mountains.
Because if I go up a mountin, I can breathe fresh air,
>> Because if I go up a mountain, I can breathe fresh air.
I can see everything on the mountin, and it feels I did a great job when I climb a mountin.
>> I can see everything from the top of the mountain, and I feel like I've done a great job whenever I will climb a mountain.