alpine, backcountry (AmE), cross-country
Backcountry skis are carefully designed to save weight.

powder, slalom
shaped

pair

put on
remove, take off
hire (BrE), rent
wax
He told me to wax my skis because he thought I was going too slowly.

pole, stick (BrE)
boot, jacket, mask, pants, suit
equipment
instructor
lesson
area, run, slope, trail
lift
jump
resort
season
chalet, lodge
holiday (BrE), trip, vacation (AmE)
She was on a ski trip in Colorado.

on skis
The children go to school on skis.

Ski is used with these nouns:
area, boot, bum, cap, goggles, hill, instructor, jacket, jump, lift, mask, rental, resort, slope, suit, track, trail, vacation