"кататься на лыжах" в инфинитиве - to ski, в прошедшем времени - skied в present continuous am/is/are skiing.
Номер 3:
1)The half past seven.
2)The quater to three.
3) A 5 o`clock
4)Quater past nine.
5)twenty minutes past one.
6)therty-five minutes past six
7)ten minutes past eight
8)five minutes to eleven
1 made 2 was wearing 3 had bought 4 are coming 5 hate 6 have been 7 agreed 8 dropped by 9 had toured 10 had been tried on
Где именно требуется объяснение?